Conformed Version

ARRANGEMENT AGREEMENT

BETWEEN

RHYOLITE RESOURCES LTD.

AND -

GOLD HART COPPER CORP.

DATED this 6th day of April, 2026

TABLE OF CONTENTS

Page

ARTICLE 1 DEFINITIONS, INTERPRETATION AND SCHEDULES ... 2
1.01 Definitions ... 2
1.02 Interpretation Not Affected by Headings ... 11
1.03 References to Articles, Sections, Etc. ... 11
1.04 Number and Gender ... 12
1.05 Date for Any Action ... 12
1.06 Statutory References ... 12
1.07 Currency ... 12
1.08 Invalidity of Provisions ... 12
1.09 Accounting Matters ... 12
1.10 Knowledge ... 12
1.11 Schedules ... 13

ARTICLE 2 THE ARRANGEMENT ... 13
2.01 Arrangement ... 13
2.02 Court Proceedings ... 13
2.03 Effecting the Arrangement ... 14
2.04 Consultation ... 15
2.05 U.S. Securities Law Matters ... 15
2.06 Closing ... 16
2.07 Adjustments for Dividends, Distributions or other Corporate Events ... 16
2.08 Withholding ... 16
2.09 Share for Share Exchange ... 16

ARTICLE 3 REPRESENTATIONS AND WARRANTIES OF RHYOLITE ... 17
3.01 Representations and Warranties of Rhyolite ... 17
3.02 Survival of Representations and Warranties ... 26

ARTICLE 4 REPRESENTATIONS AND WARRANTIES OF HART ... 27
4.01 Representations and Warranties of HART ... 27
4.02 Survival of Representations and Warranties ... 37

ARTICLE 5 COVENANTS ... 37
5.01 Covenants of Rhyolite ... 37
5.02 Covenants of HART ... 44

ARTICLE 6 CONDITIONS ... 47
6.01 Mutual Conditions ... 47
6.02 Rhyolite Conditions ... 48
6.03 HART Conditions ... 49
6.04 Nomination Right ... 50
6.05 Notice and Cure Provisions ... 50

ARTICLE 7 NON-SOLICITATION, RIGHT TO MATCH, TERMINATION FEE AND EXPENSES ... 51
7.01 Non-Solicitation ... 51
7.02 Notification of Acquisition Proposals ... 52
7.03 Responding to an Acquisition Proposal ... 53

TABLE OF CONTENTS
(continued)

Page

7.04 Right to Match ... 53
7.05 Permitted Disclosure ... 55
7.06 Termination Fee ... 56
7.07 Access to Information ... 57
7.08 Confidentiality ... 57

ARTICLE 8 TERM, TERMINATION, AMENDMENT AND WAIVER ... 58
8.01 Term ... 58
8.02 Termination ... 58
8.03 Amendment or Waiver ... 60

ARTICLE 9 GENERAL ... 61
9.01 Privacy ... 61
9.02 Notices ... 61
9.03 Remedies ... 62
9.04 Expenses ... 62
9.05 Time of the Essence ... 63
9.06 Entire Agreement ... 63
9.07 Further Assurances ... 63
9.08 Governing Law ... 63
9.09 Execution in Counterparts ... 64
9.10 No Personal Liability ... 64
9.11 Enurement and Assignment ... 64

SCHEDULE "A" PLAN OF ARRANGEMENT UNDER SECTION 193 OF PART 15 OF THE BUSINESS CORPORATIONS ACT (ALBERTA) ... A-1

ARTICLE 1 DEFINITIONS AND INTERPRETATION ... A-1
1.01 Definitions ... A-1
1.02 Interpretation Not Affected By Headings ... A-3
1.03 References to Articles, Sections, Etc. ... A-3
1.04 Number and Gender ... A-3
1.05 Date for Any Action ... A-3
1.06 Statutory References ... A-3
1.07 Currency ... A-4

ARTICLE 2 ARRANGEMENT AGREEMENT ... A-4
2.01 Arrangement Agreement ... A-4

ARTICLE 3 ARRANGEMENT ... A-4
3.01 Arrangement ... A-4
3.02 Post-Effective Time Procedures ... A-4
3.03 No Fractional HART Shares ... A-5
3.04 Transfers Free and Clear ... A-5
3.05 Binding Effect ... A-5

ARTICLE 4 DISSENT PROCEDURES ... A-5
4.01 Rights of Dissent ... A-5
4.02 Recognition of Dissenting Holders ... A-6

ii -

TABLE OF CONTENTS
(continued)

Page

ARTICLE 5 DELIVERY OF HART SHARES ... A-6
5.01 Delivery of HART Shares ... A-6
5.02 Lost Certificates ... A-6
5.03 Distributions with Respect to Unsurrendered Certificates ... A-7
5.04 Withholding Rights ... A-7
5.05 Limitation and Proscription ... A-7
5.06 U.S. Securities Laws Exemption ... A-8

ARTICLE 6 AMENDMENTS ... A-8
6.01 Amendments to Plan of Arrangement ... A-8

ARTICLE 7 FURTHER ASSURANCES ... A-9
7.01 Further Assurances ... A-9

SCHEDULE "B" FORM OF ARRANGEMENT RESOLUTION ... B-1

iii -

ARRANGEMENT AGREEMENT

THIS AGREEMENT dated the 6th day of April, 2026

BETWEEN:

RHYOLITE RESOURCES LTD.,
a corporation existing under the laws of the Province of Alberta
(hereinafter referred to as "Rhyolite")
- and -

GOLD HART COPPER CORP.,
a corporation existing under the laws of the Province of British Columbia
(hereinafter referred to as "HART")

RECITALS:

WHEREAS Rhyolite and HART have entered into a binding letter agreement dated February 17, 2026 as amended and restated on March 5, 2026 (the "Letter Agreement") setting out the principal terms upon which, among other things, HART will acquire all of the Rhyolite Shares in exchange for HART Shares (as such terms are defined herein);

WHEREAS the Rhyolite Board (as defined herein) has, taking into account, among other things, the recommendation of the Rhyolite Board and an opinion from the financial advisor to Rhyolite that the Arrangement Consideration (as defined herein) is fair, from a financial point of view, to the Rhyolite Shareholders (as defined herein), determined that the Arrangement (as defined herein) is in the best interests of Rhyolite;

AND WHEREAS the Rhyolite Board has approved the Arrangement and other transactions contemplated by this Arrangement Agreement and determined to recommend approval of the Arrangement Resolution to the Rhyolite Shareholders;

AND WHEREAS the HART Board has approved the transactions contemplated by this Arrangement Agreement;

AND WHEREAS Rhyolite and HART intend that the proposed business combination be effected by way of the Plan of Arrangement under the provisions of the Business Corporations Act (Alberta), and in furtherance of such business combination, the Rhyolite Board has agreed to submit the Arrangement Resolution to the Rhyolite Shareholders and the Court for approval;

NOW THEREFORE THIS AGREEMENT WITNESSES THAT, in consideration of the mutual covenants and agreements herein contained and for other good and valuable consideration, the receipt and sufficiency of which is hereby acknowledged by each of the Parties, the Parties hereby agree as follows:

ARTICLE 1

DEFINITIONS, INTERPRETATION AND SCHEDULES

1.01 Definitions

In this Arrangement Agreement, unless the context otherwise requires, the following words and terms with the initial letter or letters thereof capitalized shall have the meanings ascribed to them below:

(a) "1933 Act" means the Securities Act of 1933 of the United States of America;

(b) "1934 Act" means the Securities Exchange Act of 1934 of the United States of America;

(d) "Acquisition Proposal" means, other than the transactions contemplated by this Arrangement Agreement, any: (i) proposal, offer or expression of interest or inquiry regarding: (A) any merger, take-over bid, amalgamation, plan of arrangement, share exchange, business combination, consolidation, recapitalization, reorganization, joint venture, partnership or similar transaction, including any single or multi-step transaction or series of related transactions involving Rhyolite that constitutes all or more than 50% of the consolidated assets of such Party or which would result in a Person or group of Persons beneficially owning or having the right to acquire 50% or more of any class of voting or equity securities of such Party on a fully diluted basis, or liquidation, dissolution or winding-up in respect of Rhyolite; (B) any sale or acquisition of all or more than 50% of the assets of Rhyolite or any material asset or material mineral property or joint venture of Rhyolite, in each case including any single or multi-step transaction or series of related transactions (or any lease, long-term supply agreement or other arrangement having the same economic effect); or (C) any sale or acquisition of all or more than 50% of the outstanding equity or other securities (or any new issuance of a material number of such securities) of Rhyolite, including any single or multi-step transaction or series of related transactions; or (ii) public announcement or disclosure of any of the foregoing or any intention to do any of the foregoing;

(e) "Applicable Securities Laws" means the Securities Act, all other applicable provincial and territorial securities Laws of Canada, the 1933 Act, the 1934 Act, all other applicable United States federal and state securities Laws, the rules, regulations and published policies under each of the foregoing securities Laws, and the applicable stock exchange and listing rules of the TSXV;

(f) "Arrangement" means an arrangement under the provisions of Section 193 of Part 15 of the ABCA on the terms and conditions set forth in the Plan of Arrangement, subject to any amendment or supplement thereto made in accordance therewith, herewith or made at the direction of the Court in the Final Order with the consent of the Parties, each acting reasonably;

(g) "Arrangement Agreement" means this arrangement agreement, together with the schedules attached hereto, as amended, amended and restated, or supplemented from time to time;

(h) "Arrangement Consideration" means one HART Share for every 2.6 Rhyolite Shares (the "Arrangement Consideration Factor");

(i) "Arrangement Resolution" means the special resolution approving the Arrangement, the Plan of Arrangement and this Arrangement Agreement to be considered by the Rhyolite Shareholders at the Rhyolite Meeting, substantially in the form set out in Schedule "B";

(j) "Authorization" means any authorization, order, permit, approval, grant, licence, registration, consent, right, notification, condition, franchise, privilege, certificate, judgment, writ, injunction, award, determination, direction, decision, decree, by-law, rule or regulation, whether or not having the force of Law and whether or not granted by a Governmental Entity;

(k) "Business Day" means any day, other than a Saturday, a Sunday or a statutory holiday in Vancouver, British Columbia, Calgary, Alberta or Toronto, Ontario;

(l) "Canadian Securities Administrators" means, collectively, the provincial and territorial securities commission or similar regulatory authority of each of the provinces and territories of Canada;

(m) "CEWS" means the Canada Emergency Wage Subsidy, enacted in section 125.7 of the Tax Act, and any other Tax related COVID-19 subsidies offered by a Governmental Entity;

(n) "CEWS Returns" means any and all returns filed, required to be filed, or required to be kept on file in respect of CEWS;

(o) "Change in Rhyolite Recommendation" shall have the meaning ascribed thereto in Subsection 5.01(b)(iv)(A);

(p) "Completion Deadline" means the date by which the Arrangement and any other transactions contemplated by this Arrangement Agreement are to be completed, which date shall be on or prior to October 31, 2026, or such later date as may be agreed to in writing by the Parties;

(q) "Concurrent Financing" means the non-brokered private placement of HART Units at a price of $0.26 per HART Unit for aggregate gross proceeds of up to $18,613,613.72, and not less than $4,000,000;

(r) "Confidential Information" means, in relation to each of the Parties (the "Discloser"):

(i) all information, in whatever form communicated or maintained, whether orally, in writing, electronically, in computer readable form or otherwise, that the Discloser discloses to, or that is gathered by inspection by, a Party (the "Recipient") or any of the Recipient's Representatives in the course of the Recipient's review of the transactions contemplated by this Agreement, whether provided before or after the date of this Agreement, including information that contains or otherwise reflects information concerning the Discloser or its businesses, affairs, financial condition, assets, liabilities, operations, prospects or activities, and specifically includes financial information, technical information, budgets, business plans, ways of doing business, business results, prospects, customer lists, forecasts, legal opinions, and any information provided to the Discloser by third parties under circumstances in which the Discloser has an obligation to protect the confidentiality of such information;

(ii) all plans, proposals, reports, analyses, notes, studies, forecasts, compilations or other information, in any form, that are based on, contain or reflect any Confidential Information regardless of the identity of the Person preparing the same (collectively, the "Notes"); and

(iii) the fact that information has been disclosed or made available to the Recipient or the Recipient's Representatives,

but does not include any information that:

(iv) is at the time of disclosure to the Recipient or thereafter becomes generally available to the public, other than as a result of a disclosure by the Recipient or any of the Recipient's Representatives in breach of this Agreement;

(v) is or was received by the Recipient on a non-confidential basis from a source other than the Discloser or its Representatives if such source is not prohibited from disclosing the information to the Recipient by a confidentiality agreement with, or a contractual, fiduciary or other legal confidentiality obligation to, the Discloser;

(vi) was known by the Recipient prior to disclosure in connection with the transactions contemplated by this Agreement and was not subject to any contractual, fiduciary or other legal confidentiality obligation on the part of the Recipient; or

(vii) is required to be disclosed by the Recipient to a court (including the Court) or other Governmental Entity, provided the Recipient provides the Discloser with such notice as is possible so that it can contest the disclosure if possible;

(s) "Court" means the Court of King's Bench of Alberta;

(t) "Depositary" means the depositary agent, to be appointed upon mutual agreement of the Parties (each acting reasonably) for the purpose of, among other things, exchanging the Rhyolite Shares for HART Shares in connection with the Arrangement;

(u) "Discloser" has the meaning set out in the definition of Confidential Information;

(v) "Effective Date" shall have the meaning ascribed thereto in Section 2.03;

(w) "Effective Time" means the Effective Time as defined in the Plan of Arrangement;

(x) "Encumbrance" includes any mortgage, pledge, assignment, charge, lien, claim, security interest, adverse interest, adverse claim, other third person interest or encumbrance of any kind, whether contingent or absolute, and any agreement, option, right or privilege (whether by Law, contract or otherwise) capable of becoming any of the foregoing;

(y) "Environmental Approvals" means all permits, certificates, licences, authorizations, consents, instructions, registrations, directions, approvals, decisions, decrees, conditions, notifications, orders, whether or not having the force of law, issued or required by any Governmental Entity pursuant to any Environmental Laws;

(z) "Environmental Laws" means all applicable Laws whether foreign or domestic, including applicable common law and civil law, for the protection of the natural environment and

human health and safety and for the regulation of contaminants, pollutants, waste, toxic and hazardous substances, and includes Environmental Approvals;

(aa) "Final Order" means the final order of the Court, in form acceptable to Rhyolite and HART, each acting reasonably, approving the Arrangement, as such order may be amended, supplemented or varied by the Court with the consent of the Parties at any time prior to the Effective Date or, if appealed, then unless such appeal is withdrawn or denied, as affirmed or as amended on appeal;

(bb) "Governmental Entity" means:

(i) any supranational body or organization, nation, government, state, province, country, territory, municipality, quasi-government, administrative, judicial or regulatory authority, agency, board, body, bureau, commission, instrumentality, court or tribunal or any political subdivision thereof, or any central bank (or similar monetary or regulatory authority) thereof, any taxing authority, any ministry or department or agency of any of the foregoing; and

(ii) any entity exercising executive, legislative, judicial, regulatory or administrative functions of, or pertaining to, government, including any court or arbitrator or any stock exchange, including the TSXV;

(cc) "HART" means Gold Hart Copper Corp., a corporation existing under the laws of the Province of British Columbia;

(dd) "HART Board" means the board of directors of HART;

(ee) "HART Equity Incentive Plan" means the equity incentive plan of HART, as approved by the HART Shareholders;

(ff) "HART Financial Statements" shall have the meaning ascribed thereto in Section 4.01(g);

(gg) "HART Options" means all options to purchase HART Shares outstanding immediately prior to the Effective Time and issued pursuant to the HART Equity Incentive Plan;

(hh) "HART Public Documents" shall have the meaning ascribed thereto in Section 4.01(e);

(ii) "HART Shareholders" means, at any applicable time, the registered or beneficial holders of HART Shares, as the context requires;

(jj) "HART Shares" means shares of common stock in the capital of HART;

(kk) "HART Subsidiaries" means, collectively, the direct and indirect wholly-owned subsidiaries of HART, including Vicunau Metals Corp. and Gold Hart Chile SpA;

(ll) "HART Unit" means a unit of HART comprised of one HART Share and one-half of one HART Unit Warrant;

(mm) "HART Unit Warrants" means the HART Warrants comprising the HART Units, with each HART Unit Warrant being exercisable to acquire one HART Share at an exercise price of $0.40 per HART Share for a period of two years from the date of issuance thereof;

(nn) "HART Warrants" means the common share purchase warrants of HART, including the HART Unit Warrants;

(oo) "IFRS" means IFRS Accounting Standards formulated by the International Accounting Standards Board, as adopted in Canada and as updated and amended from time to time;

(pp) "in the Ordinary Course of Business" means and refers to the normal day-to-day operations of the business with respect to the particular Party, consistent with past practice of such Party, provided in any event such action is not unreasonable;

(qq) "Interim Order" means the interim order of the Court pursuant to the ABCA, made in connection with the Arrangement, as such order may be amended, supplemented or varied by the Court with the consent of the Parties, each acting reasonably;

(rr) "Laws" means any laws, including supranational, national, provincial, state, municipal and local civil, commercial, banking, Tax, personal and real property, security, mining, environmental, water, energy, investment, property ownership, land use and zoning, sanitary, occupational health and safety laws, treaties, statutes, ordinances, judgments, decrees, injunctions, writs, certificates and orders, by- laws, rules, regulations, ordinances, that are binding upon or applicable to such Person or its business, undertaking, property or securities, and to the extent that they have the force of law, protocols, codes, guidelines, policies, notices, directions or other requirements of any Governmental Entity;

(ss) "Letter Agreement" has the meaning ascribed thereto in the recitals to this Agreement;

(tt) "Material Adverse Change" or "Material Adverse Effect" means, in respect of any Party, any one or more changes, conditions, circumstances, events, effects, developments, facts or occurrences which, individually or in the aggregate: (i) is, or would reasonably be expected to be, material and adverse to the business, properties, assets (tangible or intangible), liabilities (including any contingent liabilities), capitalization, condition (financial or otherwise) or results of operations of that Party and its subsidiaries taken as a whole; or (ii) prevents or materially impairs, or would reasonably be expected to prevent or materially impair, the ability of that Party to perform its obligations under this Arrangement Agreement, in each case other than any change, condition, circumstance, event, effect, development, fact or occurrence:

(i) relating to the economy, financial or political conditions or securities markets in general, globally, in Canada, the United States or Chile;

(ii) the occurrence of any natural disaster, social disorder, outbreak of hostilities or any terrorist attack globally, in Canada, the United States or Chile;

(iii) affecting the mining industry in general globally, in Canada, the United States or Chile;

(iv) resulting from changes in the market price of base or precious metals or other commodities relating to changes in currency exchange rates, interest rates, monetary policy or inflation;

(v) any actions taken (or omitted to be taken) pursuant to this Arrangement Agreement or at the written request, or with the prior written consent, of the other Party hereto;

(vi) relating to any generally applicable change in Laws or the interpretation or application of same (other than orders, judgments or decrees against that Party or any of its subsidiaries) or generally applicable change in IFRS;

(vii) any epidemics, pandemics or disease outbreak or other public health condition (excluding COVID-19 or any variation or worsening thereof), earthquakes, volcanoes, tsunamis, hurricanes, tornadoes or other natural disasters or similar occurrence;

(viii) resulting from the announcement of the execution of this Arrangement Agreement and the transactions contemplated hereby;

(ix) relating to a change in the market price or trading volume of the shares of that Party (provided that the cause(s) of such change may be taken into account in determining whether a Material Adverse Change or Material Adverse Effect has occurred); or

(x) the execution, announcement or performance of this Agreement or the Arrangement or the implementation of the Arrangement,

provided, however, that such effect referred to in clause (i), (ii), (iii), (iv), (v), (vi) or (vii) above does not materially disproportionately affect that Party and its Subsidiaries, taken as a whole, relative to comparable exploration and/or mining companies;

(uu) "MI 61-101" means Multilateral Instrument 61-101 – Protection of Minority Security Holders in Special Transactions;

(vv) "Muckahi Royalty" means the 10% gross revenue royalty of any party from the use of the Muckahi Mining System up to $10,000,000 in proceeds, in accordance with the terms and conditions of a royalty agreement dated January 25, 2023;

(ww) "Notes" has the meaning set out in paragraph (ii) of the definition of Confidential Information;

(xx) "Notifiable Transaction" shall have the meaning ascribed thereto in subsection 237.4(1) of the Tax Act;

(yy) "Parties" means, collectively, HART and Rhyolite;

(zz) "Person" means an individual, partnership, association, body corporate, joint venture, business organization, trustee, executor, administrative legal representative, Governmental Entity or any other entity, whether or not having legal status;

(aaa) "Plan of Arrangement" means the plan of arrangement, the form of which is set out as Schedule "A" to this Arrangement Agreement, and any amendments or variations made in accordance with this Arrangement Agreement or the Plan of Arrangement or made at the direction of the Court in the Final Order with the prior written consent of the Parties, each acting reasonably;

(bbb) "Recipient" has the meaning set out in the definition of Confidential Information;

(ccc) "Reportable Transaction" shall have the meaning ascribed thereto in subsection 237.3(1) of the Tax Act;

(ddd) "Representative" when used with respect to a Person means each director, officer, employee, professional advisor and other agent or representative of that Person;

(eee) "Rhyolite" means Rhyolite Resources Ltd., a corporation existing under the ABCA;

(fff) "Rhyolite Benefit Plans" means all plans with respect to Rhyolite employees or service providers or former employees or former service providers which Rhyolite is a party to or bound by or to which Rhyolite may have any direct or indirect liability relating to retirement savings, pensions, bonuses, equity awards, profit sharing, deferred compensation, incentive compensation, life or accident insurance, hospitalization, health, medical or dental treatment or expenses, disability, unemployment insurance benefits, employee loans, vacation pay, severance or termination pay or other benefits (other than those benefits provided solely under a statutory benefit plan which Rhyolite is required to participate in or comply with, including the Canada Pension Plan and plans administered pursuant to applicable health tax, workplace safety insurance and employment insurance legislation);

(ggg) "Rhyolite Board" means the board of directors of Rhyolite;

(hhh) "Rhyolite Circular" means the notice of the Rhyolite Meeting and accompanying management information circular, including all schedules thereto and documents incorporated by reference therein, to be sent to Rhyolite Shareholders in connection with the Rhyolite Meeting, as amended, supplemented or otherwise modified from time to time in accordance with the terms of this Arrangement Agreement;

(iii) "Rhyolite Director Nominee" has the meaning ascribed thereto in Section 6.04(a);

(jjj) "Rhyolite Dissent Procedures" means the procedures set out in the Plan of Arrangement to be taken by a Rhyolite Shareholder in exercising Rhyolite Dissent Rights;

(kkk) "Rhyolite Dissent Rights" means the rights of dissent in respect of the Arrangement as contemplated in the Plan of Arrangement;

(lll) "Rhyolite Dissenting Shareholders" means registered Rhyolite Shareholders as at the record date who have duly and validly exercised their Rhyolite Dissent Rights in strict compliance with the Rhyolite Dissent Procedures and whose Rhyolite Dissent Rights have not terminated;

(mmm) "Rhyolite Fairness Opinion" shall have the meaning ascribed thereto in Section 3.01(d);

(nnn) "Rhyolite Financial Statements" shall have the meaning ascribed thereto in Section 3.01(h);

(ooo) "Rhyolite Locked-Up Shareholders" means the Persons who are parties to the Rhyolite Standstill and Lock-Up Agreements;

(ppp) "Rhyolite Material Contracts" shall have the meaning ascribed thereto in Section 3.01(q)(i);

(qqq) "Rhyolite Meeting" means the annual and special meeting, including any adjournments or postponements thereof, of the Rhyolite Shareholders to be held, among other things, to consider and, if deemed advisable, to approve the Arrangement Resolution;

(rrr) "Rhyolite Public Documents" shall have the meaning ascribed thereto in Section 3.01(f);

(sss) "Rhyolite Recommendation" shall have the meaning ascribed thereto in Section 3.01(d);

(ttt) "Rhyolite Representatives" shall have the meaning ascribed thereto in Section 7.01(a);

(uuu) "Rhyolite Shareholders" means, at any applicable time, the registered or beneficial holders of Rhyolite Shares, as the context requires;

(vvv) "Rhyolite Shareholder Approval" shall have the meaning ascribed to such term in Subsection 2.02(a)(iii);

(www) "Rhyolite Shares" means common shares in the capital of Rhyolite;

(xxx) "Rhyolite Standstill and Lock-Up Agreements" means the standstill and lock-up agreements to be entered into on or before the Effective Date and made between HART and the Rhyolite Locked-Up Shareholders, to be in form and substance satisfactory to HART, acting reasonably, setting forth the terms and conditions upon which they have agreed, among other things, to (i) comply with customary standstill restrictions preventing such shareholder from directly or indirectly making any unsolicited takeover bid, requisitioning or contesting a meeting of the holders of HART Shares, or otherwise materially affecting control of HART; and (ii) not sell, transfer, assign, or otherwise dispose of any HART Shares that it acquired from HART as of the Effective Date, for a period of 6 months following the Effective Date (subject to customary exceptions);

(yyy) "Rhyolite Stock Option Plan" means the incentive stock option plan of Rhyolite;

(zzz) "Rhyolite Termination Fee" means a cash termination payment in an amount equal to $250,000 payable by Rhyolite to HART upon the occurrence of a Rhyolite Termination Fee Event;

(aaaa) "Rhyolite Termination Fee Event" shall have the meaning ascribed thereto in Section 7.06(a);

(bbbb) "Rhyolite Voting Support Agreements" means the voting support agreements dated within five (5) Business Days of the date of this Agreement between HART and the Supporting Shareholders setting forth the terms and conditions upon which they have

10 -

agreed, among other things, to vote their Rhyolite Shares in favour of the Arrangement Resolution;

(cccc) "Right to Match" shall have the meaning ascribed thereto in Section 1.1(a)(iv)(A);

(dddd) "Section 3(a)(10) Exemption" means the exemption from the registration requirements of the 1933 Act pursuant to Section 3(a)(10) thereof;

(eeee) "Securities Act" means the Securities Act (Alberta);

(ffff) "SEDAR+" means the System for Electronic Document Analysis and Retrieval;

(gggg) "Superior Proposal" means any unsolicited bona fide written Acquisition Proposal made on or after the date of this Agreement and prior to the approval of the Arrangement Resolution at the Rhyolite Meeting from an arm's length third party to acquire, directly or indirectly, all, and not less than all, of the outstanding Rhyolite Shares for the same form and amount of consideration per Rhyolite Share (provided such amount is greater than the Arrangement Consideration) or all or substantially all of the assets of Rhyolite that:

(i) complies with Securities Laws in all material respects and did not result from or involve a breach of Article 7;

(ii) is reasonably capable of being completed, without undue delay, taking into account all financial, legal, regulatory, timing and other aspects of such Acquisition Proposal and the Person or group of Persons making such Acquisition Proposal;

(iii) is not subject to a financing condition and, in respect of which it has been demonstrated to the satisfaction of the Rhyolite Board, in its good-faith judgment, after receiving the advice of its outside legal counsel and financial advisors, that adequate arrangements have been made in respect of any financing required to complete such Acquisition Proposal, which shall require either (A) cash resources on hand available to fund the Acquisition Proposal or (B) binding financing commitments (which may be subject only to customary conditions relating to completion of definitive transaction documentation) that are available on or prior to the proposed time of completion of the Acquisition Proposal;

(iv) is not subject to a due diligence or access condition; and

(v) the Rhyolite Board determines, in its good-faith judgment, after receiving the advice of its outside legal counsel and financial advisors and after taking into account all legal, financial, regulatory and other aspects of such Acquisition Proposal and the Person or group of Persons making such Acquisition Proposal, including the risk of non-completion, would, if consummated in accordance with its terms, having considered the risk of non-completion, result in a transaction that is more favourable, from a financial point of view, to the Rhyolite Shareholders than the Plan of Arrangement (including any amendments to the terms and conditions of the Plan of Arrangement proposed by HART pursuant to Section Error! Reference source not found.);

(hhhh) "Superior Proposal Notice" shall have the meaning ascribed thereto in Section 7.04(a)(iii);

11 -

(iii) "Supporting Shareholders" means, those Rhyolite Shareholders that have entered into Rhyolite Voting Support Agreements;

(jjjj) "Tax" and "Taxes" means all federal, state, local, provincial, branch or other taxes, including income taxes, gross receipts taxes, windfall profits taxes, ad valorem taxes, property taxes, capital taxes, net worth taxes, production taxes, licence taxes, excise taxes, franchise taxes, employment taxes, sales taxes, use taxes, value added taxes, transfer taxes, withholding or similar taxes, payroll taxes, employment taxes, pension plan premiums, social security premiums, workers' compensation premiums, employment insurance or compensation premiums, stamp taxes, occupation taxes, premium taxes, mining taxes, alternative or add-on minimum taxes, goods and services taxes, customs duties or other taxes of any kind whatsoever imposed or charged by any Governmental Entity, together with any interest, penalties or additions with respect thereto, and any interest in respect of such penalties or additions;

(kkkk) "Tax Act" means the Income Tax Act (Canada);

(llll) "Tax Returns" means all returns, schedules, elections, declarations, reports, information returns, notices, forms, statements and other documents made, prepared or filed with any Governmental Entity or required to be made, prepared or filed with any Governmental Entity relating to Taxes;

(mmmm) "Third Party Confidentiality Agreement" shall have the meaning ascribed to such term in Subsection 7.03(b)(iv)(A);

(nnnn) "Transaction Personal Information" shall have the meaning ascribed thereto in Section 9.01;

(oooo) "TSXV" means the TSX Venture Exchange;

(pppp) "Working Capital Certificate" has the meaning ascribed thereto in 5.01(s).

1.02 Interpretation Not Affected by Headings

The division of this Arrangement Agreement into articles, sections, subsections, paragraphs and subparagraphs and the insertion of headings herein are for convenience of reference only and shall not affect in any way the meaning or interpretation of this Arrangement Agreement. The terms "this Arrangement Agreement", "hereof", "herein", "hereto", "hereunder" and similar expressions refer to this Arrangement Agreement and the schedules attached hereto and not to any particular article, section or other portion hereof and include any agreement, schedule or instrument supplementary or ancillary hereto or thereto. References in this Arrangement Agreement to the words "include", "includes" or "including" shall be deemed to be followed by the words "without limitation".

1.03 References to Articles, Sections, Etc.

Unless otherwise indicated, references in this Arrangement Agreement to any article, section, subsection, paragraph, subparagraph or portion thereof are a reference to the applicable article, section, subsection, paragraph, subparagraph or portion thereof in this Arrangement Agreement.

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1.04 Number and Gender

In this Arrangement Agreement, unless the context otherwise requires, words importing the singular only shall include the plural and vice versa, and words importing the use of any gender shall include all genders.

1.05 Date for Any Action

If the date on which any action is required to be taken hereunder by any Party is not a Business Day, such action shall be required to be taken on the next succeeding day that is a Business Day.

1.06 Statutory References

Any reference in this Arrangement Agreement to a statute includes all regulations and rules made thereunder, all amendments to such statute or regulation in force from time to time and any statute or regulation that supplements or supersedes such statute or regulation.

1.07 Currency

Unless otherwise stated, all references in this Arrangement Agreement to amounts of money are expressed in lawful money of Canada, and "$" refers to Canadian dollars.

1.08 Invalidity of Provisions

Each of the provisions contained in this Arrangement Agreement is distinct and severable and a declaration of invalidity or unenforceability of any such provision or part thereof by a court of competent jurisdiction shall not affect the validity or enforceability of any other provision hereof. To the extent permitted by applicable Law, the Parties waive any provision of Law that renders any provision of this Arrangement Agreement or any part thereof invalid or unenforceable in any respect. The Parties shall engage in good faith negotiations to replace any provision hereof or any part thereof that is declared invalid or unenforceable with a valid and enforceable provision or part thereof, so as to effect the original intent of the Parties as closely as possible in an acceptable manner to the end that the Arrangement and any other transactions contemplated by this Arrangement Agreement are fulfilled to the fullest extent possible.

1.09 Accounting Matters

Unless otherwise stated, all accounting terms used in this Arrangement Agreement shall have the meanings attributable thereto under IFRS and all determinations of an accounting nature required to be made hereunder shall be made in a manner consistent therewith.

1.10 Knowledge

Where the phrases "to the knowledge of Rhyolite" or "to Rhyolite's knowledge" or "to the knowledge of HART" or "to HART's knowledge" are used in respect of Rhyolite or HART, as the case may be, such phrase shall mean, in respect of each representation and warranty or other statement which is qualified by such phrase, that such representation and warranty or other statement is being made based upon: (i) in the case of Rhyolite, the collective actual knowledge of Richard A. Graham, Chief Executive Officer and a director of Rhyolite, after reasonable inquiry; and (ii) in the case of HART, the actual knowledge of Isaac Maresky, Chief Executive Officer and director of HART, after reasonable inquiry.

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1.11 Schedules

The following schedules are attached to, and are deemed to be incorporated into and form part of, this Arrangement Agreement:

Schedule	Matter
Schedule "A"	Plan of Arrangement
Schedule "B"	Form of Arrangement Resolution

ARTICLE 2

THE ARRANGEMENT

2.01 Arrangement

Rhyolite and HART agree that the Arrangement shall be implemented in accordance with and subject to the terms and conditions contained in this Arrangement Agreement and the Plan of Arrangement. The Parties agree that: (i) the Arrangement shall result in the acquisition by HART of all of the issued and outstanding Rhyolite Shares; and (ii) each Rhyolite Shareholder (other than a Rhyolite Shareholder who has validly exercised its Rhyolite Dissent Rights) shall be entitled to receive, in exchange for each Rhyolite Share held, the Arrangement Consideration, all as more specifically set out in the Plan of Arrangement.

2.02 Court Proceedings

Rhyolite shall apply to the Court, in a manner acceptable to HART, acting reasonably, pursuant to the ABCA for the Interim Order and the Final Order as follows:

(a) as soon as reasonably practicable after the date of execution of this Arrangement Agreement and in any case on or before April 30, 2026, and subject to Section 5.01(a), Rhyolite shall file, proceed with and diligently prosecute an application to the Court for the Interim Order which shall request that the Interim Order shall provide, among other things:

(i) for the class of Persons to whom notice is to be provided in respect of the Arrangement and the Rhyolite Meeting and for the manner in which such notices are to be provided, such notices to include, inter alia, that such Persons have a right to appear at the hearing before the Court at which the fairness of the Arrangement is to be adjudged;

(ii) for confirmation of the record date for purposes of determining the Rhyolite Shareholders entitled to receive notice of and vote at the Rhyolite Meeting;

(iii) that the requisite approval for the Arrangement Resolution shall be: (A) at least 66⅔% of the votes cast on the Arrangement Resolution by the Rhyolite Shareholders, voting as a single class, present in person or by proxy at the Rhyolite Meeting; and (B) if applicable, a simple majority of the votes cast on the Arrangement Resolution by Rhyolite Shareholders, voting as a single class, present in person or by proxy at the Rhyolite Meeting (excluding Rhyolite Shares held by any "interested parties" and "related parties" of any interested parties (as such terms are defined in MI 61-101) in accordance with the requirements of MI 61-101) (collectively, the "Rhyolite Shareholder Approval");

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(iv) that, in all other respects, except as modified by the Interim Order, the terms, conditions and restrictions of the Rhyolite constating documents, including quorum requirements and other matters, shall apply in respect of the Rhyolite Meeting;

(v) that HART intends to rely upon the Section 3(a)(10) Exemption in connection with the issuance of HART Shares to be issued in exchange for securities as contemplated by the Arrangement, subject to and conditioned upon the Court's determination following a hearing that the Arrangement is fair and reasonable to the Rhyolite Shareholders;

(vi) for the grant of the Rhyolite Dissent Rights to the registered holders of Rhyolite Shares;

(vii) for notice requirements with respect to the presentation of the application to the Court for the Final Order;

(viii) that the Rhyolite Meeting may be adjourned or postponed from time to time by management of Rhyolite with the consent of HART, such consent not be unreasonably withheld, in accordance with the terms of this Arrangement Agreement, without the need for additional approval of the Court;

(ix) that, subject to the Interim Order and with the consent of HART, such consent not be unreasonably withheld, the record date for the Rhyolite Shareholders entitled to notice of and to vote at the Rhyolite Meeting will not change in respect of any adjournment(s) (or postponements) of the Rhyolite Meeting; and

(x) for such other matters as Rhyolite and HART, each acting reasonably and with the prior consent of the other, may require; and

(b) subject to obtaining the approvals as contemplated by the Interim Order and as may be directed by the Court in the Interim Order, Rhyolite shall take all steps necessary or desirable to apply for and obtain the Final Order as soon as practicable following approval of the Arrangement Resolution at the Rhyolite Meeting.

The notices of motion and related materials for the applications referred to in this Section 2.02 shall be in a form satisfactory to Rhyolite and HART, each acting reasonably.

2.03 Effecting the Arrangement

The Arrangement shall become effective at the Effective Time: (a) on the date the Final Order is deposited at the registered office of Rhyolite (the "Effective Date") which date shall be the date that is three Business Days after the satisfaction or waiver (subject to applicable Laws) of the conditions set forth in Article 6 (other than the delivery of items to be delivered on the Effective Date and the satisfaction of those conditions that, by their terms, cannot be satisfied until immediately prior to the Effective Date); or (b) such date as mutually agreed in writing by the Parties. Subject to the rights of termination contained in Article 8, upon the Rhyolite Shareholders providing the Rhyolite Shareholder Approval in accordance with the Interim Order, Rhyolite obtaining the Final Order and the other conditions contained in Article 6 being complied with or waived, Rhyolite shall deposit the Final Order at the registered office of Rhyolite, whereupon the Arrangement and other transactions contemplated by this Arrangement Agreement shall occur and shall be deemed to have occurred in the order set out in the Plan of Arrangement without any further act or formality.

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2.04 Consultation

Rhyolite and HART will consult with each other in respect to issuing any press release or otherwise making any public statement with respect to this Arrangement Agreement or the Arrangement and in making any filing with the Court, any Governmental Entity, Canadian Securities Administrator or stock exchange with respect thereto. Each of Rhyolite and HART shall use its commercially reasonable efforts to enable each of the other of them to review and comment on all such press release and filings prior to the release or filing, respectively, thereof; provided, however, that the obligations herein will not prevent a Party from making, after consultation with the other Party, such disclosure as is required by Applicable Securities Laws or the rules and policies of any applicable stock exchange.

2.05 U.S. Securities Law Matters

The Parties agree that the HART Shares to be issued to the Rhyolite Shareholders pursuant to the Arrangement will not be registered under the 1933 Act and will be issued in reliance on the Section 3(a)(10) Exemption. In order to ensure the availability of the Section 3(a)(10) Exemption, the Parties agree that the Arrangement will be carried out on the following basis:

(a) prior to the issuance of the Interim Order, the Court will be advised of the intention of the Parties to rely on the Section 3(a)(10) Exemption with respect to the issuance of the HART Shares as the Arrangement Consideration in connection with the Arrangement, based on the Court's approval of the Arrangement;

(b) the Court will be asked to satisfy itself that the Arrangement is fair and reasonable to the Rhyolite Shareholders;

(c) the hearing of the Court to give approval of the Arrangement must be open to any Persons to whom securities will be issued under the Arrangement and there will not be any improper impediments to the appearance by those Persons at the hearing;

(d) Rhyolite will ensure that each Rhyolite Shareholder entitled to receive HART Shares as the Arrangement Consideration pursuant to the Arrangement will be given adequate notice advising them of their right to attend the hearing for the Final Order and providing them with sufficient information necessary for them to exercise that right;

(e) the Rhyolite Shareholders will be advised that HART Shares issued as Arrangement Consideration pursuant to the Arrangement have not been registered under the 1933 Act and will be issued by HART in reliance on the Section 3(a)(10) Exemption, and may be subject to restrictions on resale under the applicable securities laws of the United States, including Rule 144 under the 1933 Act with respect to affiliates of Rhyolite and HART;

(f) the Interim Order approving the Rhyolite Meeting shall specify that each Person to whom HART Shares will be issued pursuant to the Arrangement will have the right to appear before the Court at the hearing for the Final Order so long as they enter an appearance within a reasonable time; and

(g) the Final Order approving the Arrangement that is obtained from the Court will expressly state that the Arrangement is approved by the Court as being fair and reasonable to the Rhyolite Shareholders, as well as the following or substantially similar language: "This Order will serve as a basis of a claim to an exemption, pursuant to section 3(a)(10) of the United States Securities Act of 1933, as amended, from the registration requirements

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otherwise imposed by that act regarding the distribution of securities of HART pursuant to the Plan of Arrangement".

2.06 Closing

The closing of the Arrangement will take place electronically at 8:00 a.m. (Toronto time) on the Effective Date.

2.07 Adjustments for Dividends, Distributions or other Corporate Events

If on or after the date hereof, either Party: (i) splits, consolidates or reclassifies any of its common shares; (ii) undertakes any other capital reorganization; or (iii) declares, sets aside or pays any dividend or other distribution to its shareholders of record as of a time prior to the Effective Date, the Parties hereto shall make such adjustments to the Arrangement, including the Arrangement Consideration and the Arrangement Consideration Factor, as they determine acting in good faith to be necessary to restore the original intention of the Parties in the circumstances. If the Parties are unable to agree on such adjustments within ten (10) Business Days, the matter shall be referred to a nationally recognized independent accounting firm. The accounting firm shall act as an expert and not as an arbitrator, and its determination shall be final, conclusive and binding on the Parties. The costs and expenses of the accounting firm shall be borne equally by the Parties.

2.08 Withholding

Rhyolite, HART and the Depositary shall be entitled to deduct or withhold from any consideration payable or otherwise deliverable to any Person hereunder and from all dividends or other distributions otherwise payable to any former Rhyolite Shareholder such amounts as Rhyolite, HART or the Depositary are required to deduct or withhold with respect to such payment under the Tax Act, the United States Internal Revenue Code of 1986, or any provision of any applicable Tax Laws. To the extent that amounts are so deducted or withheld, such deducted or withheld amounts shall be treated for all purposes hereof as having been paid to the relevant Person in respect of which such deduction or withholding was made, provided that such deducted or withheld amounts are remitted to the appropriate Governmental Entity. Each of Rhyolite, HART and the Depositary and any person acting on their behalf is hereby authorized to sell or otherwise dispose of such portion of the Arrangement Consideration as is necessary to provide sufficient funds to Rhyolite, HART or the Depositary, as the case may be, to enable it to implement such deduction or withholding, and Rhyolite, HART or the Depositary will notify the holder thereof and remit to the holder any unapplied balance of the net proceeds of such sale. None of Rhyolite, HART or the Depositary shall be liable for any loss arising out of any such sale.

2.09 Share for Share Exchange

The Parties intend that the exchange of Rhyolite Shares in exchange for HART Shares pursuant to the Plan of Arrangement shall be structured as a tax-deferred share-for-share exchange pursuant to subsection

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85.1(1) of the Tax Act, subject to a Rhyolite Shareholder's option to choose to recognize its capital gain (or capital loss) in the manner provided in subsection 85.1(1) of the Tax Act.

ARTICLE 3

REPRESENTATIONS AND WARRANTIES OF RHYOLITE

3.01 Representations and Warranties of Rhyolite

Rhyolite hereby represents and warrants to HART as set forth in this Section 3.01 and hereby acknowledges that HART is relying upon such representations and warranties in connection with entering into this Arrangement Agreement and agreeing to complete the Arrangement.

(a) Organization

(i) Rhyolite has been duly incorporated under the ABCA, is validly existing and has all necessary corporate power, authority and capacity to own its property and assets and to carry on its business as currently owned and conducted.

(ii) Rhyolite is duly qualified or licensed to do business and is in good standing in each jurisdiction where the character of the properties owned, leased or operated by it or the nature of its business makes such qualification or licensing necessary, except where the failure to be so qualified, licensed or in good standing has not had, or would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect in respect of Rhyolite.

(b) Capitalization

(i) The authorized capital of Rhyolite consists of an unlimited number of Rhyolite Shares. As at the date of this Arrangement Agreement, 107,185,253 Rhyolite Shares are issued and outstanding. As at the date of this Arrangement Agreement, there are no options, warrants, conversion privileges or other rights, agreements, arrangements or commitments (pre-emptive, contingent or otherwise) obligating Rhyolite to issue or sell any securities of Rhyolite securities or obligations of any kind convertible into, or exchangeable or exercisable for, any securities of Rhyolite.

(ii) All outstanding Rhyolite Shares have been duly authorized. The outstanding Rhyolite Shares are validly issued and outstanding as fully paid and non-assessable shares, free of pre-emptive rights.

(iii) Rhyolite has no Subsidiaries. Rhyolite does not own, directly or indirectly, any equity interest, voting securities, or other ownership interest in any corporation, partnership, limited liability company, joint venture, trust, association, or other entity.

(iv) There are no outstanding bonds, debentures or other evidences of indebtedness of Rhyolite having the right to vote (or that are convertible for, or exercisable into, securities having the right to vote) with the Rhyolite Shareholders on any matter. There are no outstanding obligations of Rhyolite to repurchase, redeem or otherwise acquire any outstanding Rhyolite Shares or with respect to the voting or disposition of any outstanding securities of Rhyolite. No holder of securities issued

by Rhyolite has any right to compel Rhyolite to register or otherwise qualify securities for public sale in Canada, the United States or elsewhere.

(i) Rhyolite has the necessary corporate power, authority and capacity to enter into this Arrangement Agreement and to perform its obligations hereunder (subject to obtaining the approval of the Rhyolite Shareholders of the Arrangement Resolution and receipt of the Interim Order and the Final Order as contemplated in Section 2.02). The execution, delivery and performance of this Arrangement Agreement by Rhyolite has been duly authorized by the Rhyolite Board and no other corporate proceedings on its part are necessary to authorize the execution, delivery and performance of this Arrangement Agreement, other than the Rhyolite Shareholder Approval. This Arrangement Agreement has been duly executed and delivered by Rhyolite and constitutes a legal, valid and binding obligation of Rhyolite, enforceable against it in accordance with its terms, subject to bankruptcy, insolvency and other applicable Laws affecting creditors' rights generally, and to general principles of equity.

(ii) The authorization of this Arrangement Agreement, the execution and delivery by Rhyolite of this Arrangement Agreement and the performance by it of its obligations under this Arrangement Agreement, and the completion of the Arrangement will not:

(A) result (with or without notice or the passage of time) in a violation or breach of or constitute a default under, require an Authorization to be obtained under or give rise to any third party right of termination, amendment, cancellation, acceleration, penalty or payment obligation or right of purchase or sale or pre-emptive or participation right under, any provision of:

(1) its articles, by-laws, or other charter documents;

(2) any applicable Laws, except to the extent that the violation or breach of any applicable Laws, would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect in respect of Rhyolite;

(3) any note, bond, mortgage, indenture, instrument, contract, agreement, lease or Authorization to which Rhyolite is party or by which it or its assets are bound, except as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect in respect of Rhyolite; or

(4) any judgment, decree, order or award of any Governmental Entity, court or arbitrator,

subject to obtaining the approval of the Rhyolite Shareholders of the Arrangement Resolution, receipt of the Interim Order and the Final Order as contemplated in Section 2.02 and receipt of TSXV conditional acceptance;

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(B) give rise to any right of termination, amendment, acceleration or cancellation of indebtedness of Rhyolite, or cause any such indebtedness to come due before its stated maturity, or cause any available credit of Rhyolite to cease to be available, or cause any security interest in any assets of Rhyolite to become enforceable or realizable;

(C) give rise to any rights of first refusal or trigger any change of control provisions or any restriction or limitation under any such note, bond, mortgage, indenture, contract, agreement or Authorization; or

(D) result in the imposition of any Encumbrance upon any assets of Rhyolite, except as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect in respect of Rhyolite.

(iii) No consent, approval, order or authorization of, or registration, declaration or filing with, any Governmental Entity or other Person is required to be obtained by Rhyolite in connection with this Arrangement Agreement and the completion of the Arrangement and any other transactions contemplated by this Arrangement Agreement, other than: (i) the Rhyolite Shareholder Approval; (ii) the approval of the Court pursuant to the Interim Order and the Final Order; (iii) the requirement to prepare and file this Arrangement Agreement and the Rhyolite Circular together with related continuous disclosure filings; (iv) the requirement to obtain TSXV conditional acceptance; and (v) such authorizations, consents, approvals and filings as to which the failure to obtain or make would not, individually or in the aggregate, prevent or materially delay the completion of the Arrangement and any other transactions contemplated by this Arrangement Agreement. To the knowledge of Rhyolite, the only Rhyolite Shareholders whose votes may not be counted for the purposes of the "majority of the minority" approval under MI 61-101 are Tyrus Capital S.A.M. (as to 18,928,864 Rhyolite Shares) and Michael George Leskovec (as to 228,500 Rhyolite Shares).

(d) Support of the Arrangement

Rhyolite has received an opinion of Evans & Evans, Inc. dated April 6, 2026 in oral form, to the effect that, as of such date and subject to the assumptions and limitations set out therein, the Arrangement is fair, from a financial point of view, to Rhyolite Shareholders (the "Rhyolite Fairness Opinion"). The Rhyolite Board has, taking into account, among other things, the Rhyolite Fairness Opinion, determined that the Arrangement is in the best interests of Rhyolite. The Rhyolite Board has approved the Arrangement and any other transactions contemplated by this Arrangement Agreement and determined to recommend approval of the Arrangement Resolution to the Rhyolite Shareholders (the "Rhyolite Recommendation").

(e) Authorizations

Rhyolite possess all Authorizations necessary to properly conduct its business. Each Authorization obtained by Rhyolite is in full force and effect and not subject to any dispute. Rhyolite is in compliance with each of such Authorizations in all material respects. In all material respects, no event has occurred which, with the giving of notice, lapse of time or both, could constitute a default under, or in respect of, any of such Authorizations.

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(f) Public Filings

Rhyolite has filed all documents or information required to be filed by it under Applicable Securities Laws from January 1, 2024 to the date of this Arrangement Agreement (the "Rhyolite Public Documents"). All of the Rhyolite Public Documents, as of their respective dates (and as of the dates of any amendments thereto), did not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading. All of the Rhyolite Public Documents, as of their respective dates (and as of the dates of any amendments thereto), complied as to both form and content in all material respects with the requirements of Applicable Securities Laws or were amended on a timely basis to correct deficiencies identified by the Canadian Securities Administrators. All of the Rhyolite Public Documents are publicly available on SEDAR+. Rhyolite has not filed any confidential material change report with any Canadian Securities Administrator that at the date hereof remains confidential.

(g) Disclosure Controls and Procedures

Rhyolite has established and maintains a system of disclosure controls and procedures designed to ensure that information required to be disclosed by Rhyolite under Applicable Securities Laws is recorded, processed, summarized and reported within the time periods specified in the Applicable Securities Laws.

(h) Financial Statements

The audited financial statements of Rhyolite (including any related notes thereto) for the fiscal years ended December 31, 2025 and 2024 (collectively, the "Rhyolite Financial Statements") have been prepared in accordance with IFRS and all applicable Laws and present fairly, in all material respects, the assets, liabilities (whether accrued, absolute, contingent or otherwise), financial position and results of operations of Rhyolite as at December 31, 2025 and 2024, and for the periods covered thereby applied on a basis consistent with the immediately prior period and throughout the periods indicated (except as may be indicated expressly in the notes thereto). The Rhyolite Financial Statements reflect appropriate and adequate reserves in accordance with IFRS in respect of contingent liabilities, if any, of Rhyolite.

(i) Internal Controls Over Financial Reporting

Rhyolite maintains internal controls over its financial reporting. Such internal controls over its financial reporting are effective in providing reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with IFRS and Applicable Securities Laws. To the knowledge of Rhyolite, prior to the date of this Arrangement Agreement: (A) there were no significant deficiencies in the design or operation of, or material weaknesses in, the internal controls over financial reporting of Rhyolite that are reasonably likely to adversely affect the ability of Rhyolite to record, process, summarize and report financial information; and (B) there was no fraud, whether or not material, that involves management or other employees who have a significant role in the internal control over financial reporting of Rhyolite. Since December 31, 2025, Rhyolite has received no: (x) complaints from any source regarding

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any material accounting, internal accounting controls or auditing matters; or (y) expressions of concern from employees of Rhyolite regarding questionable accounting or auditing matters.

(j) Liabilities and Indebtedness

Rhyolite does not have any liabilities or obligations of any nature (whether accrued, absolute, contingent or otherwise), except for: (i) liabilities and obligations that are specifically disclosed in the Rhyolite Financial Statements; or (ii) liabilities and obligations incurred in the Ordinary Course of Business since December 31, 2025. Rhyolite does not have any material obligation to issue any debt securities, or guarantee, endorse or otherwise become responsible for, the obligations of any other Person. Rhyolite does not have any off balance sheet liabilities or other arrangements that would avoid disclosure of liabilities in the Rhyolite Financial Statements.

(k) Books and Records

(i) The financial books, records and accounts of Rhyolite in all material respects:

(A) have been maintained in accordance with applicable Laws and IFRS on a basis consistent with prior years;

(B) are stated in reasonable detail and accurately and fairly reflect the material transactions involving, or any acquisitions or dispositions of, any material assets of Rhyolite; and

(ii) The corporate minute book of Rhyolite is complete and accurate in all material respects and contains, among other things, copies of minutes of all meetings and resolutions of the respective directors (other than those portions of minutes of meetings reflecting discussions of the Arrangement) and securityholders held in accordance with applicable Laws, and share issuance and transfer records.

(iii) Rhyolite has provided to HART, on or before the date hereof, a true and complete copy of the minute book of Rhyolite (including all of the information referred to in Section 3.01(k)(ii) above).

(l) Absence of Certain Changes or Events

Since December 31, 2025, to the date of this Arrangement Agreement, except as disclosed in the Rhyolite Public Documents, and other than for the purposes of the Arrangement and any other transactions contemplated by this Arrangement Agreement:

(i) Rhyolite has conducted its business only in the Ordinary Course of Business;

(ii) there has not been any acquisition or sale by Rhyolite of any material property or assets;

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(iii) there has not occurred one or more changes, events or occurrences which would, individually or in the aggregate, be reasonably likely to result in a Material Adverse Effect in respect of Rhyolite;

(iv) there has been no dividend or distribution of any kind declared, paid or made by Rhyolite on any Rhyolite Shares;

(v) Rhyolite has not effected or passed any resolution to approve a split, consolidation or reclassification of any of the outstanding Rhyolite Shares;

(vi) Rhyolite has not incurred any liabilities or obligations of any nature (whether accrued, absolute, contingent or otherwise) which would, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect in respect of Rhyolite;

(vii) there has not been any incurrence, assumption or guarantee by Rhyolite of any debt for borrowed money, any creation or assumption by Rhyolite of any Encumbrance, or any making by Rhyolite of any loan, advance or capital contribution to, or investment in, any other Person, which would, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect in respect of Rhyolite; and

(viii) Rhyolite has not effected any change in its accounting methods, principles or practices.

(m) No Default

Rhyolite is not in default under, and there exists no event, condition or occurrence which, after notice or lapse of time or both, would constitute such a default or would trigger a right of termination under: (i) any note, bond, mortgage, indenture or other instrument evidencing any indebtedness to which Rhyolite is a party; or (ii) any other contract, agreement, lease, letter of intent, offer or Authorization or other instrument or obligation, which would, individually or in the aggregate, be reasonably expected to have a Material Adverse Effect in respect of Rhyolite.

(n) Litigation

(i) There is no claim, action, proceeding or investigation that has been commenced or is pending or, to the knowledge of Rhyolite, threatened, against Rhyolite or affecting any of its properties or assets by or before any Governmental Entity which, if determined adversely to Rhyolite, would, individually or in the aggregate:

(A) reasonably be expected to result in liability to Rhyolite in excess of $50,000 or have a Material Adverse Effect in respect of Rhyolite; or

(B) reasonably be expected to prevent or materially delay the completion of the Arrangement or any other transactions contemplated under the Arrangement Agreement;

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nor is Rhyolite aware of any existing ground on which any such liability may be incurred or claim, action, proceeding or investigation might be commenced with any reasonable likelihood of success.

(ii) Neither Rhyolite, nor any of its properties and assets, is subject to any outstanding judgment, order, writ, injunction or decree which would reasonably be expected to have a Material Adverse Effect in respect of Rhyolite or to prevent or materially delay the completion of the Arrangement.

(o) Employment Matters

(i) No Person is a party to or a participant in any agreement, arrangement, plan, obligation or understanding providing for severance, termination or other payments in connection with the termination of the employment or engagement of, or resignation of, any director, officer or employee of, or independent contractor to, Rhyolite following a change of control of Rhyolite (other than statutory severance obligations) and there are no written or oral agreements, arrangements, plans, obligations or understandings providing for severance or termination or other payments in connection with the termination of the employment or engagement of, or resignation of, any director, officer or employee of, or independent contractor to, Rhyolite following a change of control of Rhyolite.

(ii) Rhyolite has no employees, and except as disclosed in the Rhyolite Public Documents or as otherwise disclosed to HART, Rhyolite is not a party to any employment, engagement or similar agreement with any director or officer of Rhyolite.

(iii) Rhyolite has not declared or paid, or committed to declare or pay, any amount to any Person in respect of a performance or incentive or other bonus in respect of all or any part of its fiscal year ended on December 31, 2025 or in connection with the completion of the Arrangement or any other transactions contemplated by this Arrangement Agreement.

(iv) Except for the Rhyolite Stock Option Plan, there exists no Rhyolite Benefit Plans and Rhyolite does not have any pension plan or other obligation to provide post-retirement benefits.

(p) Tax Matters

(i) Except as would not, individually or in the aggregate, result in a Material Adverse Effect with respect to Rhyolite:

(A) Rhyolite has duly and in a timely manner filed all income and other material Tax Returns required to be filed by it and all such Tax Returns are correct and complete in all material respects and fully disclose the income and expenses as required by applicable Law.

(B) Rhyolite has paid on a timely basis and in all material amounts all Taxes, including instalments, which are due and payable, and has paid all assessments and reassessments, and all other Taxes, governmental charges, penalties, interest and fines due and payable by it, other than those

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which are being contested in good faith and in respect of which adequate reserves have been provided in the Rhyolite Financial Statements in accordance with IFRS.

(C) Adequate provision has been made on the Rhyolite Financial Statements for amounts at least equal to the amount of all Taxes assessed and all Taxes owing by Rhyolite that are not yet due and payable and that relate to periods ending on or prior to the date of this Arrangement Agreement, including income taxes and related deferred taxes, in conformity with IFRS and all other applicable accounting rules and principles.

(D) To the knowledge of Rhyolite, no deficiencies exist or have been asserted with respect to Taxes of Rhyolite and there are no actions, suits, proceedings, investigations or claims outstanding, pending or threatened against Rhyolite in respect of Taxes or assessments, nor are there any matters under discussion with any Governmental Entity relating to Taxes.

(E) Rhyolite has not undertaken, participated in or been contractually obligated to participate in any Reportable Transaction or Notifiable Transaction.

(ii) Rhyolite has furnished or made available to HART complete and accurate copies of all Tax returns, and any amendments thereto, filed by Rhyolite for the preceding three (3) taxation years.

(iii) To the knowledge of Rhyolite, no transaction or arrangement between Rhyolite, on the one hand, and any Person with whom Rhyolite was not dealing at arm's length, within the meaning of the Tax Act, on the other hand, involving the acquisition, delivery, disposition or provision of property or services or the right to use property or services, has taken place for consideration that is other than the fair market value of such property, services or right to use property or services and each such transaction or arrangement was made on arm's length terms and conditions.

(iv) There are no circumstances existing and no transactions or series of transactions or events has occurred which has resulted or which may result in the application of Sections 17, 78, 79 or 80 to 80.04 of the Tax Act or any equivalent provincial Tax Law to Rhyolite.

(v) Rhyolite has:

(A) duly and timely completed and filed all CEWS Returns required to be filed by it, or that it elected to file, and all such CEWS Returns are complete and correct in all material respects; and

(B) not claimed CEWS to which it was not entitled.

(vi) Rhyolite has not issued shares that are, or were intended to be, "flow-through shares" for purposes of the Tax Act in the previous two calendar years and Rhyolite does not have outstanding obligations to incur or renounce "Canadian exploration

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expenses" (within the meaning of the Tax Act) pursuant to any subscription agreements relating to the issuance of flow-through shares.

(q) Material Contracts

(i) Rhyolite has provided HART true and complete copies of all contracts to which it is a party or to which its assets are bound that are material to its property, assets or operations (the "Rhyolite Material Contracts").

(ii) All Rhyolite Material Contracts are legal, valid, binding and in full force and effect and are enforceable by Rhyolite in accordance with their respective terms (subject to bankruptcy, insolvency and other applicable Laws affecting creditors' rights generally, and to general principles of equity). Rhyolite has performed in all material respects all respective obligations required to be performed by it to date under the Rhyolite Material Contracts and has not received notice that it is alleged to be, (with or without the lapse of time or the giving of notice, or both) in breach or default in any material respect thereunder. To the knowledge of Rhyolite, no other party to any Rhyolite Material Contract is in breach of any of its material obligations thereunder or has provided written notice of its intention to terminate any such Rhyolite Material Contract.

(r) Related Party Transactions

Rhyolite is not indebted to any director, officer, employee or agent of, or independent contractor to, Rhyolite or any of its respective affiliates or associates (except for amounts due as normal salaries and bonuses and in reimbursement of ordinary expenses, or amounts which for which payment is not yet due). No director, officer, employee or agent of Rhyolite or any of its respective affiliates or associates is a party to any loan, contract, arrangement or understanding or other transactions with Rhyolite.

(s) Royalty Interest

(i) Rhyolite is the absolute legal and beneficial owner of, and has good and valid title to, the Muckahi Royalty, free and clear of any Encumbrance and defects of title.

(ii) The Muckahi Royalty is the only royalty interest that is considered to be material to Rhyolite.

(iii) There is no Contract, option, commitment or other right in favour of, or held by, any person to acquire the Muckahi Royalty or any portion thereof.

(iv) The Muckahi Royalty is in good standing and in full force and effect, enforceable by Rhyolite in accordance with its terms, and no notice of any default or breach of the Muckahi Royalty has been received by Rhyolite.

(t) Assets and Properties; Business Activities

Except for (i) the Muckahi Royalty and (ii) cash and cash equivalents, Rhyolite does not own, hold, or have any right, title, or interest, whether legal or beneficial, directly or indirectly, in or to any material property or assets of any nature whatsoever. Rhyolite does not currently carry on, and has not since December 31, 2024 carried on, any active business,

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operations or undertaking of any kind other than holding the Muckahi Royalty and managing its affairs incidental thereto.

(u) No Brokers

Except for the fee to be paid to Evans & Evans, Inc. pursuant to its engagement letter dated February 19, 2026 with Rhyolite, a true and complete copy of which has been delivered to HART, Rhyolite is not obligated to pay any brokerage fees, finder's fees, financial advisory fees, agent's commissions or other similar forms of compensation in connection with the Arrangement or any other transactions contemplated by this Arrangement Agreement.

(v) Compliance with Laws

(i) Rhyolite has complied with any applicable Laws in all material respects and is not violation of any applicable Laws in any material respects, other than non-compliance or violations which would not be material to Rhyolite, or which would not materially impair the ability of Rhyolite to perform its obligations hereunder or reasonably be expected to prevent or materially delay the completion of the Arrangement.

(ii) Neither Rhyolite, nor, to the knowledge of Rhyolite, any of the Rhyolite Representatives: (i) has used or is using any corporate funds for any illegal contributions, gifts, entertainment or other expenses relating to political activity that would be illegal; (ii) has used or is using any corporate funds for any direct or indirect illegal payments to any foreign or domestic governmental officials or employees; (iii) has violated or is violating any provision of the United States Foreign Corrupt Practices Act of 1977, the Corruption of Foreign Public Officials Act (Canada) or any similar Laws of other jurisdictions; (iv) has established or maintained, or is maintaining, any illegal fund of corporate monies or other properties; or (v) has made any bribe, illegal rebate, illegal payoff, influence payment, kickback or other illegal payment of any nature.

(w) Reporting Issuer Status

Rhyolite is a reporting issuer within the meaning of Applicable Securities Laws in Alberta, British Columbia, and Ontario and is not on the list of reporting issuers in default maintained by any of the Canadian Securities Administrators.

3.02 Survival of Representations and Warranties

The representations and warranties contained in this Article 3 shall survive the execution and delivery of this Arrangement Agreement and shall expire and be terminated and extinguished on the earlier of the Effective Date and the date on which this Arrangement Agreement is terminated in accordance with its terms. This Section 3.02 will not limit any covenant or agreement of the Parties, which, by its terms, contemplates performance after the Effective Date or the date on which this Arrangement Agreement is terminated, as the case may be. Any investigation by HART and any of its advisors shall not mitigate, diminish or affect the representations and warranties of Rhyolite contained in this Arrangement Agreement.

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ARTICLE 4

REPRESENTATIONS AND WARRANTIES OF HART

4.01 Representations and Warranties of HART

HART hereby represents and warrants to Rhyolite as set forth in this Section 4.01, and hereby acknowledges that Rhyolite is relying upon such representations and warranties in connection with entering into this Arrangement Agreement and agreeing to complete the Arrangement.

(a) Organization

(i) HART and each HART Subsidiary has been duly incorporated or formed under the applicable Laws of its jurisdiction of incorporation or formation, is validly existing and has all necessary corporate power, authority and capacity to own its property and assets and to carry on its business as currently owned and conducted. All of the HART Subsidiaries and HART's percentage of ownership of such HART Subsidiaries are as set out in the HART Public Documents. All of the outstanding shares of the HART Subsidiaries which are held directly or indirectly by HART are validly issued, fully paid and non-assessable and are owned directly or indirectly by HART free and clear of any Encumbrances. HART does not hold any equity interest, or right to acquire any equity interest, in any Person, other than its interests in the HART Subsidiaries as disclosed in the HART Public Documents.

(ii) HART and each HART Subsidiary is duly qualified or licensed to do business and is in good standing in each jurisdiction where the character of the properties owned, leased or operated by it or the nature of its business makes such qualification or licensing necessary, except where the failure to be so qualified, licensed or in good standing has not had, or would not reasonably be expected to have, individually or in the aggregate, a Material Adverse Effect in respect of HART.

(iii) HART has no Subsidiaries other than the HART Subsidiaries as disclosed in the HART Public Documents.

(b) Capitalization

(i) The authorized capital of HART consists of an unlimited number of HART Shares, of which, as at the date of this Arrangement Agreement, 183,235,832 HART Shares are issued and outstanding. As at the date of this Arrangement Agreement, there are outstanding HART Options exercisable to acquire an aggregate of up to 9,820,000 HART Shares and HART Warrants exercisable to acquire an aggregate of up to 62,979,189 HART Shares. Except as set out above, there are no options, warrants, conversion privileges or other rights, agreements, arrangements or commitments (pre-emptive, contingent or otherwise) obligating HART or any HART Subsidiary to issue or sell any securities of HART or any HART Subsidiary or securities or obligations of any kind convertible into or exchangeable or exercisable for any shares of HART or any HART Subsidiary.

(ii) All outstanding HART Shares and the HART Shares to be issued on the exercise of the HART Options and the HART Warrants have been duly authorized. The outstanding HART Shares are, and the HART Shares to be issued on the exercise

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of HART Options and the HART Warrants will be when issued, validly issued and outstanding as fully paid and non-assessable shares, free of pre-emptive rights.

(iii) There are no outstanding bonds, debentures or other evidences of indebtedness of HART or any HART Subsidiary having the right to vote (or that are convertible for, or exercisable into, securities having the right to vote) with the HART Shareholders on any matter. There are no outstanding obligations of HART or any HART Subsidiary to repurchase, redeem or otherwise acquire any outstanding HART Shares or with respect to the voting or disposition of any outstanding securities of HART or any HART Subsidiary. No holder of securities issued by HART or any HART Subsidiary has any right to compel HART or any HART Subsidiary to register or otherwise qualify securities for public sale in Canada, the United States or elsewhere.

(i) HART has the necessary corporate power, authority and capacity to enter into this Arrangement Agreement and to perform its obligations hereunder. The execution, delivery and performance of this Arrangement Agreement by HART has been duly authorized by the HART Board and no other corporate proceedings on its part are necessary to authorize the execution, delivery and performance of this Arrangement Agreement. This Arrangement Agreement has been duly executed and delivered by HART and constitutes a legal, valid and binding obligation of HART, enforceable against it in accordance with its terms, subject to bankruptcy, insolvency and other applicable Laws affecting creditors' rights generally, and to general principles of equity.

(ii) The authorization of this Arrangement Agreement, the execution and delivery by HART of this Arrangement Agreement and the performance by it of its obligations under this Arrangement Agreement, and the completion of the Arrangement will not:

(1) its or any HART Subsidiary's articles, notice of articles or other charter documents;

(3) any note, bond, mortgage, indenture, instrument, contract, agreement, lease or Authorization to which HART or any HART Subsidiary is party or by which it is bound, except as would not,

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individually or in the aggregate, reasonably be expected to have a Material Adverse Effect in respect of HART; or

(4) any judgment, decree, order or award of any Governmental Entity, court or arbitrator;

(B) other than as set out in the HART Public Documents, give rise to any right of termination, amendment, acceleration or cancellation of indebtedness of HART or any HART Subsidiary, or cause any such indebtedness to come due before its stated maturity, or cause any available credit of HART or any HART Subsidiary to cease to be available, or cause any security interest in any assets of HART or any HART Subsidiary to become enforceable or realizable, except as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect in respect of HART;

(C) other than as set out in the HART Public Documents, give rise to any rights of first refusal or trigger any change of control provisions or any restriction or limitation under any such note, bond, mortgage, indenture, contract, agreement, or Authorization described in Section 4.01(c)(ii)(A)(2), except as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect in respect of HART; or

(D) result in the imposition of any Encumbrance upon any assets of HART or any HART Subsidiary, except as would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect in respect of HART.

(iii) No consent, approval, order or authorization of, or registration, declaration or filing with, any Governmental Entity is required to be obtained by HART in connection with this Arrangement Agreement and the completion of any other transactions contemplated by this Arrangement Agreement, other than: (i) any approvals required by the Interim Order and the Final Order; (ii) the approval of the TSXV of the listing of the HART Shares issuable pursuant to the Arrangement; and (iii) such authorizations, consents, approvals and filings as to which the failure to obtain or make would not, individually or in the aggregate, prevent or materially delay the completion of the Arrangement and any other transactions contemplated by this Arrangement Agreement.

(d) Authorizations

Except as would not have a Material Adverse Effect with respect to HART: (i) HART and each HART Subsidiary possess all Authorizations necessary to properly conduct their respective businesses; (ii) each Authorization obtained by HART or any HART Subsidiary is in full force and effect and not subject to any dispute; (iii) HART and the HART Subsidiaries are in compliance with each of such Authorizations; and (iv) no event has occurred which, with the giving of notice, lapse of time or both, could constitute a default under, or in respect of, any of such Authorizations.

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(e) Public Filings

HART has filed all documents or information required to be filed by it under Applicable Securities Laws from March 18, 2025 to the date of this Arrangement Agreement (the "HART Public Documents"). All of the HART Public Documents, as of their respective dates (and as of the dates of any amendments thereto), did not contain any untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they were made, not misleading. All of the HART Public Documents, as of their respective dates (and as of the dates of any amendments thereto), complied as to both form and content in all material respects with the requirements of Applicable Securities Laws or were amended on a timely basis to correct deficiencies identified by Canadian Securities Administrators. All of the HART Public Documents are publicly available on SEDAR+. HART has not filed any confidential material change report or similar such report with any Canadian Securities Administrator that at the date hereof remains confidential.

(f) Disclosure Controls and Procedures

HART has established and maintains a system of disclosure controls and procedures designed to ensure that information required to be disclosed by HART under Applicable Securities Laws is recorded, processed, summarized and reported within the time periods specified in the Applicable Securities Laws.

(g) Financial Statements

The audited consolidated financial statements of HART (including any related notes thereto) for the fiscal years ended December 31, 2024 and 2023 and the condensed interim consolidated financial statements of HART (including any related notes thereto) for the period ended September 30, 2025 (collectively, the "HART Financial Statements") have been prepared in accordance with IFRS and all applicable Laws and present fairly, in all material respects, the assets, liabilities (whether accrued, absolute, contingent or otherwise), financial position and results of operations of HART as at December 31, 2024 and 2023 and September 30, 2025, as applicable, and for the periods covered thereby applied on a basis consistent with the immediately prior period and throughout the periods indicated (except as may be indicated expressly in the notes thereto), and subject in the case of unaudited interim consolidated financial statements to recurring year-end audit adjustments normal in nature and extent. The HART Financial Statements reflect appropriate and adequate reserves in accordance with IFRS in respect of contingent liabilities, if any, of HART.

(h) Internal Controls Over Financial Reporting

HART maintains internal controls over its financial reporting. Except as disclosed in the HART Public Documents, such internal controls over its financial reporting are effective in providing reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with IFRS and Applicable Securities Laws. To the knowledge of HART, except as disclosed in the HART Public Documents, prior to the date of this Arrangement Agreement: (A) there were no material weaknesses in the internal controls over financial reporting of HART that are reasonably likely to adversely affect the ability of HART to record, process, summarize and report financial information; and (B) there was no fraud, whether or not material, that

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involves management or other employees who have a significant role in the internal control over financial reporting of HART. Except as disclosed in the HART Public Documents, since March 18, 2025, HART has received no: (x) complaints from any source regarding any material accounting, internal accounting controls or auditing matters; or (y) expressions of concern from employees of HART regarding questionable accounting or auditing matters.

(i) Liabilities and Indebtedness

Neither HART nor any of the HART Subsidiaries have any liabilities or obligations of any nature (whether accrued, absolute, contingent or otherwise), except for: (i) liabilities and obligations that are specifically disclosed in the HART Financial Statements; (ii) liabilities and obligations incurred in the Ordinary Course of Business since September 30, 2025; or (iii) liabilities and obligations that would not have a Material Adverse Effect with respect to HART. Neither HART nor the HART Subsidiaries have any material obligation to issue any debt securities, or guarantee, endorse or otherwise become responsible for, the obligations of any other Person. Neither HART nor any of the HART Subsidiaries has any off balance sheet liabilities or other arrangements that would avoid disclosure of liabilities in the HART Financial Statements.

(j) Books and Records

(i) The financial books, records and accounts of HART and each of the HART Subsidiaries in all material respects:

(A) have been maintained in accordance with applicable Laws and IFRS on a basis consistent with prior years;

(B) are stated in reasonable detail and accurately and fairly reflect the material transactions involving, or any acquisitions or dispositions of, any assets of HART and the HART Subsidiaries; and

(ii) The corporate minute books of HART and each of the HART Subsidiaries are complete and accurate in all material respects and contain, among other things, copies of minutes of all meetings and resolutions of the respective directors (other than those portions of minutes of meetings reflecting discussions of the Arrangement) and securityholders, held in accordance with applicable Laws, and share issuance and transfer records.

(iii) HART has provided to Rhyolite, on or before the date hereof, a true and complete copy of the minute books of HART and each of the HART Subsidiaries (including all information referred to in Section 4.01(j)(ii)).

(k) Absence of Certain Changes or Events

From March 18, 2025 to the date of this Arrangement Agreement, except as disclosed in the HART Public Documents, and other than for the purposes of the Arrangement and any other transactions contemplated by this Arrangement Agreement:

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(i) HART and each of the HART Subsidiaries has conducted its business only in the Ordinary Course of Business;

(ii) there has not been any acquisition or sale by HART of any material property or assets;

(iii) there has not occurred one or more changes, events or occurrences which would, individually or in the aggregate, be reasonably likely to result in a Material Adverse Effect in respect of HART;

(iv) there has been no dividend or distribution of any kind declared, paid or made by HART on any HART Shares;

(v) HART has not effected or passed any resolution to approve a split, consolidation or reclassification of any of the outstanding HART Shares;

(vi) neither HART nor any HART Subsidiary has incurred any liabilities or obligations of any nature (whether accrued, absolute, contingent or otherwise) which would, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect in respect of HART;

(vii) there has not been any incurrence, assumption or guarantee by HART or any HART Subsidiary of any debt for borrowed money, any creation or assumption by HART or any HART Subsidiary of any Encumbrance, or any making by HART or any HART Subsidiary of any loan, advance or capital contribution to, or investment in, any other Person, which would, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect in respect of HART; and

(viii) HART has not effected any change in its accounting methods, principles or practices.

(l) No Default

Neither HART nor any of the HART Subsidiaries, nor, to the knowledge of HART, any other party thereto, is in default under, and there exists no event, condition or occurrence which, after notice or lapse of time or both, would constitute such a default or would trigger a right of termination under: (i) any note, bond, mortgage, indenture or other instrument evidencing any indebtedness to which HART or any HART Subsidiary is a party; or (ii) any other contract, agreement, lease, letter of intent, offer or Authorization or other instrument or obligation, which would, individually or in the aggregate, be reasonably expected to have a Material Adverse Effect in respect of HART.

(m) Litigation

(i) There is no claim, action, proceeding or investigation that has been commenced or is pending or, to the knowledge of HART, threatened, against HART or any HART Subsidiary or affecting any of its properties or assets before any Governmental Entity which, if determined adversely to HART or any HART Subsidiary, as the case may be, would, individually or in the aggregate reasonably be expected to prevent or materially delay the completion of the Arrangement, nor is HART aware

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of any existing ground on which any such claim, action, proceeding or investigation might be commenced with any reasonable likelihood of success.

(ii) Neither HART nor any of the HART Subsidiaries, nor any of their respective properties and assets, is subject to any outstanding judgment, order, writ, injunction or decree which would reasonably be expected to have a Material Adverse Effect in respect of HART or to prevent or materially delay the completion of the Arrangement or any other transactions contemplated by this Arrangement Agreement.

(n) Tax Matters

Except as would not, individually or in the aggregate, result in a Material Adverse Effect with respect to HART:

(i) HART and each of the HART Subsidiaries has duly and in a timely manner filed all material Tax Returns required to be filed by it and all such Tax Returns are correct and complete in all material respects and fully disclose the income and expenses as required by applicable Law.

(ii) HART and each of the HART Subsidiaries has paid on a timely basis and in all material amounts all Taxes, including instalments, which are due and payable, and has paid all assessments and reassessments, and all other Taxes, governmental charges, penalties, interest and fines due and payable by it, other than those which are being contested in good faith and in respect of which adequate reserves have been provided in the HART Financial Statements in accordance with IFRS.

(iii) Adequate provision has been made on the HART Financial Statements for amounts at least equal to the amount of all Taxes assessed and all Taxes owing by HART or any HART Subsidiary that are not yet due and payable and that relate to periods ending on or prior to the date of this Arrangement Agreement, including income taxes and related deferred taxes, in conformity with IFRS and all other applicable accounting rules and principles.

(iv) No deficiencies exist or have been asserted with respect to Taxes of HART or any HART Subsidiary and, to the knowledge of HART, there are no actions, suits, proceedings, investigations or claims outstanding, pending or threatened against HART or any HART Subsidiary in respect of Taxes or assessments or any matters under discussion with any Governmental Entity relating to Taxes.

(v) Neither HART nor any HART Subsidiary has undertaken, participated in or has been contractually obligated to participate in any Reportable Transaction or Notifiable Transaction.

(vi) There are no circumstances existing and no transactions or series of transactions or events has occurred which has resulted or which may result in the application of Sections 17, 78, 79 or 80 to 80.04 of the Tax Act or any equivalent provincial Tax Law to Hart or any HART Subsidiary.

(vii) To the knowledge of HART, no transaction or arrangement between HART, on the one hand, and any Person with whom HART was not dealing at arm's length,

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within the meaning of the Tax Act, on the other hand, involving the acquisition, delivery, disposition or provision of property or services or the right to use property or services, has taken place for consideration that is other than the fair market value of such property, services or right to use property or services and each such transaction or arrangement was made on arm's length terms and conditions.

(viii) HART and each of the HART Subsidiaries has:

(A) duly and timely completed and filed all CEWS Returns required to be filed by it, or that it elected to file, and all such CEWS Returns are complete and correct in all material respects; and

(B) not claimed CEWS to which it was not entitled.

(ix) HART has not issued shares that are, or were intended to be, "flow-through shares" for purposes of the Tax Act in the previous two calendar years and HART does not have outstanding obligations to incur or renounce "Canadian exploration expenses" or "Canadian development expenses" (within the meaning of the Tax Act) pursuant to any subscription agreements relating to the issuance of flow-through shares.

(o) Property and Mineral Rights; Operations

With respect to the HART Properties and other mineral interests and rights (including any material claims, concessions, exploration licences, exploitation licences, mining leases or prospecting permits relating to the HART Properties (collectively, the "HART Mineral Rights"), except as disclosed in the HART Public Documents and except where it would not reasonably be expected to have a Material Adverse Effect in respect of HART:

(i) HART or a HART Subsidiary is the sole legal and beneficial owner of all right, title and interest in and to the HART Properties and the HART Mineral Rights, free and clear of any Encumbrances;

(ii) all of the HART Mineral Rights have been properly located and recorded in compliance with applicable Law and are comprised of valid and subsisting mineral claims;

(iii) the disclosure set out in the HART Public Documents with respect to the HART Mineral Rights has been prepared in accordance with the applicable requirements of NI 43-101 and HART has no actual knowledge that such disclosure is inaccurate in any material respect;

(iv) the HART Properties and the HART Mineral Rights are in good standing under applicable Law and, to the knowledge of HART, all work required to be performed and filed in respect thereof has been performed and filed, all Taxes, rentals, fees, expenditures and other payments in respect thereof have been paid or incurred and all filings in respect thereof have been made;

(v) there is no adverse claim against or challenge to the title to or ownership of the HART Properties or any of the HART Mineral Rights;

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(vi) either HART or a HART Subsidiary has the exclusive right to deal with the HART Properties and all of the HART Mineral Rights;

(vii) no Person other than HART and the HART Subsidiaries has any interest in the HART Properties or any of the HART Mineral Rights or the production or profits therefrom or any royalty in respect thereof or any right to acquire any such interest;

(viii) there are no back-in rights, earn-in rights, rights of first refusal or similar provisions or rights which would affect HART's interest in the HART Properties or any of the HART Mineral Rights;

(ix) there are no material restrictions on the ability of HART and the HART Subsidiaries to use, transfer or exploit the HART Properties or any of the HART Mineral Rights, except pursuant to applicable Laws; and

(x) neither HART nor any HART Subsidiary has received any notice, whether written or oral, from any Governmental Entity of any revocation or intention to revoke any interest of HART in any of the HART Properties or any of the HART Mineral Rights.

(p) Environmental

Except for any matters that, individually or in the aggregate, could not reasonably be expected to have a Material Adverse Effect in respect of HART:

(i) all facilities and operations of HART and the HART Subsidiaries and their predecessors have been conducted, and are now, in material compliance with all Environmental Laws;

(ii) there have been no spills, releases, deposits, presence or discharges of pollutants or hazardous or toxic substances, contaminants or wastes into or in the earth, air or any body of water, whether surface or otherwise, by HART or any of the HART Subsidiaries or their predecessors or at, to or from HART's assets or operations, which could reasonably be expected to result in liability or remediation obligations under any Environmental Law;

(iii) neither HART nor any of the HART Subsidiaries has failed to report to the proper Governmental Entity the occurrence of any event which is required to be so reported by any Environmental Law;

(iv) no environmental, reclamation or closure obligation, demand, notice, work order or other liabilities presently exist with respect to any portion of any currently or formerly owned, leased, used or otherwise controlled property, interests and rights or relating to the operations and business of HART and the HART Subsidiaries and, to the knowledge of HART, there is no basis for any such obligations, demands, notices, work orders or liabilities to arise in the future as a result of any activity in respect of such property, interests, rights, operations and business;

(v) neither HART nor any HART Subsidiary is subject to any proceeding, application, order or directive which relates to environmental, health or safety matters, and which may require any material work, repairs, construction or expenditures;

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(vi) HART and the HART Subsidiaries are in possession of, and in material compliance with, all Environmental Approvals, consents, waivers, permits, orders and exemptions required to own, lease and operate its properties and mineral projects and to conduct its business as it is now being conducted, and neither HART nor any of the HART Subsidiaries has received any notification from any Governmental Entity pursuant to any Environmental Laws that any work, undertaking, study, report, assessment, repairs, construction or other expenditures are required to be made by it as a condition of continued compliance with any Environmental Laws, or any Environmental Approvals issued pursuant thereto, or that any Environmental Approvals referred to above are about to be reviewed, made subject to limitation or conditions, revoked, withdrawn or terminated; and

(vii) to the knowledge of HART, none of HART nor any of the HART Subsidiaries is subject to any past or present fact, condition or circumstance that could reasonably be expected to result in liability under any Environmental Laws.

(q) Compliance with Laws

(i) HART and the HART Subsidiaries have complied with, and are not in violation of any applicable Laws, other than non-compliance or violations which would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect with respect to HART, or which would not materially impair the ability of HART to perform its obligations hereunder or reasonably be expected to prevent or materially delay the completion of the Arrangement.

(ii) Neither HART, nor, to the knowledge of HART, any of its directors, officers, representatives, agents or employees: (i) has used or is using any corporate funds for any illegal contributions, gifts, entertainment or other expenses relating to political activity that would be illegal; (ii) has used or is using any corporate funds for any direct or indirect illegal payments to any foreign or domestic governmental officials or employees; (iii) has violated or is violating any provision of the United States Foreign Corrupt Practices Act of 1977, Corruption of Foreign Public Officials Act (Canada) or any similar Laws of other jurisdictions; (iv) has established or maintained, or is maintaining, any illegal fund of corporate monies or other properties; or (v) has made any bribe, illegal rebate, illegal payoff, influence payment, kickback or other illegal payment of any nature.

(r) Stock Exchange Compliance

HART is in compliance in all material respects with the applicable listing and corporate governance rules and regulations of the TSXV.

(s) Reporting Issuer Status

HART is a reporting issuer within the meaning of Applicable Securities Laws in the provinces of British Columbia and Alberta and is not on the list of reporting issuers in default maintained by any of the Canadian Securities Administrators.

(t) Certain Securities Law Matters

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The HART Shares to be issued in connection with the Arrangement: (i) will not be subject to any statutory hold or restricted period under the Applicable Securities Laws in Canada and will be freely tradable within Canada by the holders thereof, subject in each case to restrictions contained in Section 2.6(3) of National Instrument 45-102 – Resale of Securities of the Canadian Securities Administrators; (ii) assuming the compliance of Rhyolite with the terms of this Arrangement Agreement, the HART Shares to be issued in connection with the Arrangement shall be exempt from registration requirements of the 1933 Act pursuant to the Section 3(a)(10) Exemption; and (iii) the HART Shares to be distributed in the United States pursuant to the Arrangement shall not be subject to resale restrictions in the United States under the 1933 Act (other than as may be prescribed by Rule 144 and Rule 145 under the 1933 Act).

4.02 Survival of Representations and Warranties

The representations and warranties contained in this Article 4 shall survive the execution and delivery of this Arrangement Agreement and shall expire and be terminated and extinguished on the earlier of the Effective Date and the date on which this Arrangement Agreement is terminated in accordance with its terms. This Section 4.02 will not limit any covenant or agreement of the Parties, which, by its terms, contemplates performance after the Effective Date or the date on which this Arrangement Agreement is terminated, as the case may be. Any investigation by Rhyolite and any of its advisors shall not mitigate, diminish or affect the representations and warranties of HART contained in this Arrangement Agreement.

ARTICLE 5 COVENANTS

5.01 Covenants of Rhyolite

Subject to the terms of this Arrangement Agreement, Rhyolite hereby covenants and agrees with HART as follows:

(a) Interim Order

As soon as reasonably practicable, and in any event no later than April 30, 2026, Rhyolite shall file, proceed with and diligently prosecute an application to the Court for the Interim Order in accordance with Section 2.02(a), and in such a manner as to preserve for HART the availability of the Section 3(a)(10) Exemption.

(b) The Rhyolite Meeting

Rhyolite shall:

(i) in a timely and expeditious manner carry out such terms of the Interim Order as are required under the terms thereof to be carried out by Rhyolite;

(ii) as promptly as practicable after the execution of this Arrangement Agreement, prepare, in compliance with the Interim Order and in consultation with HART, the Rhyolite Circular (which shall be in a form satisfactory to each of the Parties and their respective legal counsel, acting reasonably), together with any other documents required by applicable Laws in connection with the Rhyolite Meeting, which shall contain all information required by, and shall otherwise comply with, all applicable Laws, including all applicable corporate Laws and Applicable

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Securities Laws (including MI 61-101), in all material respects, and the Rhyolite Fairness Opinion of its independent financial advisor. The Rhyolite Circular and the other documents referred to above shall provide Rhyolite Shareholders with information in sufficient detail to permit them to form a reasoned judgment with respect to the matters placed before them at the Rhyolite Meeting, and shall ensure that no information included therein (other than with respect to any information relating to and provided by HART) contains any misrepresentation (as defined under Applicable Securities Laws);

(iii) as promptly as practicable after obtaining the Interim Order, cause the Rhyolite Circular and all other related materials for the Rhyolite Meeting to be mailed to Rhyolite Shareholders and any other Persons required by the Interim Order and in accordance with all applicable Laws in all material respects and file with the Canadian Securities Administrators the Rhyolite Circular and all other related materials for the Rhyolite Meeting, and if necessary in order to comply with Applicable Securities Laws, after the Rhyolite Circular shall have been so mailed, promptly circulate amended, supplemental or supplemented proxy materials, and, if required in connection therewith, re-solicit proxies;

(iv) Rhyolite shall:

(A) (I) take all commercially reasonable lawful action to solicit proxies in favour of the Arrangement Resolution; (II) take all commercially reasonable actions to seek the approval of the Arrangement Resolution by Rhyolite Shareholders; (III) include its unanimous recommendation to vote in favour of the Arrangement Resolution in the Rhyolite Circular and include in the Rhyolite Circular a statement that each director and executive officer of Rhyolite intends to vote all of such Person's Rhyolite Shares in favour of the Arrangement Resolution, subject to the other terms of this Arrangement Agreement and the Rhyolite Voting Support Agreements; (IV) not: (x) withdraw, modify or qualify, or propose publicly to withdraw, modify or qualify, in any manner adverse to HART, or fail to reaffirm its recommendation of the Arrangement within five (5) Business Days (and in any case prior to the Rhyolite Meeting) after having been requested in writing by HART to do so, the approval or recommendation of the Rhyolite Board of this Arrangement Agreement or the Arrangement; or (y) approve, recommend or remain neutral with respect to, or propose publicly to approve, recommend or remain neutral with respect to, any Acquisition Proposal (it being understood that publicly taking no position or a neutral position with respect to an Acquisition Proposal until the earlier of (i) five (5) Business Days following the public announcement of such Acquisition Proposal, or (ii) one (1) Business Day prior to the Rhyolite Meeting shall not be considered an adverse modification) (either (x) or (y) being a "Change in Rhyolite Recommendation"), in either case except as expressly permitted by Article 7;

(B) promptly notify HART if at any time before the Effective Date Rhyolite becomes aware that: (i) the Rhyolite Circular contains a misrepresentation (as defined under Applicable Securities Laws); or (ii) an amendment or

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supplement to the Rhyolite Circular is required, and the Parties shall cooperate in the preparation of any amendment or supplement;

(C) convene and conduct the Rhyolite Meeting in accordance with the articles and by-laws of Rhyolite, the Interim Order, the ABCA and applicable Laws as soon as reasonably practicable and in any event no later than June 30, 2026;

(D) not propose or submit for consideration at the Rhyolite Meeting any special business other than the Arrangement Resolution without the prior written consent of HART (which consent shall not be unreasonably withheld, conditioned or delayed); and

(E) provide notice to HART of the Rhyolite Meeting and all material steps in the application before the Court and allow representatives of HART to attend the Rhyolite Meeting;

(v) take all such actions as may be required under the Interim Order or applicable Laws, including the rules of the TSXV, in connection with the Arrangement and any other transactions contemplated by this Arrangement Agreement.

Rhyolite shall use its commercially reasonable efforts to advise HART, upon request by HART, and in any event at least on a daily basis on each of the ten (10) Business Days prior to the date of the Rhyolite Meeting, as to the aggregate tally of the proxies received by Rhyolite in respect of the Arrangement Resolution.

(d) Adjournment

Subject to the terms of this Arrangement Agreement, Rhyolite shall not adjourn, postpone or cancel the Rhyolite Meeting (or propose to do so), except: (i) if a quorum is not present at the Rhyolite Meeting; (ii) if required by applicable Laws or a ruling, order or decree of a court having jurisdiction, any Governmental Entity, Canadian Securities Administrator, or any stock exchange; or (iii) if otherwise agreed to by HART, acting reasonably, in writing.

(e) Dissent Rights

Rhyolite shall provide HART with copies of any purported exercise of the Rhyolite Dissent Rights and all written communications with any Rhyolite Shareholder purportedly exercising such Rhyolite Dissent Rights, and shall not settle or compromise any Rhyolite Dissent Rights or any other legal action brought by any present, former or purported Rhyolite Shareholder in connection with the Arrangement and any other transactions contemplated by this Arrangement Agreement, without the prior written consent of HART, which consent shall not be unreasonably withheld.

(f) Amendments to Rhyolite Circular

In a timely manner and subject to providing HART with a reasonable opportunity to comment thereon, Rhyolite shall, with the assistance of HART, prepare and file any

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mutually agreed (or as otherwise required by applicable Laws) amendments or supplements to the Rhyolite Circular (which amendments or supplements shall be in a form acceptable to HART and Rhyolite, each acting reasonably) with respect to the Rhyolite Meeting and mail such amendments or supplements, as required by the Interim Order and in accordance with all applicable Laws, to all Rhyolite Shareholders and other Persons required by the Interim Order to be sent such amendments and supplements to all jurisdictions where such amendments or supplements are required to be mailed, complying in all material respects with all applicable Laws on the date of the mailing thereof.

(g) Final Order

Subject to the approval of the Arrangement Resolution in accordance with the provisions of the Interim Order and as required by applicable Laws, Rhyolite shall in a timely manner, file, proceed with and diligently prosecute an application for the Final Order, which application shall be in form and substance satisfactory to HART and Rhyolite, each acting reasonably.

(h) Compliance with Orders

In a timely and expeditious manner, Rhyolite shall take all such actions and do all such acts and things as are specified in the Interim Order, the Plan of Arrangement and the Final Order to be taken or done by Rhyolite.

(i) Copy of Documents

Rhyolite shall furnish promptly to HART a copy of each material notice, report, schedule or other document or communication delivered, filed or received by Rhyolite in connection with this Arrangement Agreement, the Arrangement, the Interim Order, the Final Order, the Rhyolite Meeting or any other meeting at which Rhyolite Shareholders are entitled to attend and vote relating to special business, any filings made under any applicable Laws and any material dealings or communications with any Governmental Entity, Canadian Securities Administrator or any stock exchange in connection with, or in any way affecting, the Arrangement and any other transactions contemplated by this Arrangement Agreement.

(j) Usual Business

Except as expressly provided herein, Rhyolite shall, conduct business only, and not take any action except, in the Ordinary Course of Business and use commercially reasonable efforts to preserve intact its present business organization and goodwill, to preserve intact the Muckahi Royalty, to keep available the services of its officers and to maintain satisfactory relationships with Persons having business relationships with Rhyolite.

(k) Certain Actions Prohibited

Other than as expressly provided for in this Arrangement Agreement, Rhyolite shall not, without the prior written consent of HART, directly or indirectly, do or permit to occur any of the following prior to the earlier of the Effective Time and the termination of this Arrangement Agreement:

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(i) split, consolidate or reclassify any of the outstanding Rhyolite Shares or undertake any other capital reorganization, or reduce the stated capital in respect of any outstanding Rhyolite Shares;

(ii) settle or compromise any claim brought by any present, former or purported Rhyolite Shareholder or any present, former or purported holder of any other securities of Rhyolite in connection with the Arrangement or any other transactions contemplated by this Arrangement Agreement, except as provided in this Arrangement Agreement;

(iii) amend its articles or by-laws or the terms of any outstanding securities of Rhyolite;

(iv) take any action that would result in any amendment, modification or change of any term of any outstanding indebtedness of Rhyolite;

(v) authorize, approve, agree to issue, issue or sell any securities, including convertible securities, or redeem, offer to purchase or purchase any of its outstanding securities;

(vi) enter into, create, declare, adopt, amend, vary, modify or take any other action with respect to any bonus, target bonus, profit sharing, incentive, salary or other compensation, equity based award, pension, retirement, deferred compensation, severance, change of control, employment or other employee benefit plan, agreement, trust fund, award or arrangement for the benefit or welfare of any officer, director or employee, or similar rights or other benefits, except for changes in compensation for employees, other than officers and directors, in the Ordinary Course of Business;

(vii) enter into any contract with a term of more than three (3) months, except in the Ordinary Course of Business;

(viii) except in the Ordinary Course of Business: (A) incur or commit to incur any indebtedness for borrowed money (except for indebtedness not to exceed $50,000 in the aggregate for working capital purposes) or issue any debt securities; (B) incur or commit to incur, or guarantee, endorse or otherwise become responsible for, any other material liability, obligation or indemnity or the obligation of any other Person (whether accrued, absolute, contingent or otherwise); or (C) make any loans or advances to any Person;

(ix) make any changes to the existing accounting policies of, other than as required by applicable Laws, Applicable Securities Laws or by IFRS;

(x) pay, discharge or satisfy any material claims, liabilities or obligations, other than the payment, discharge or satisfaction of liabilities or obligations in the Ordinary Course of Business as they become due in accordance with their terms;

(xi) engage in any transaction with any related parties, other than in the Ordinary Course of Business or as contemplated by the Arrangement or any other transactions contemplated by this Arrangement Agreement or as disclosed in the Rhyolite Public Documents;

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(xii) cause its current insurance policies within its control or any of the coverage thereunder to lapse, unless simultaneously with such termination, cancellation or lapse, replacement policies underwritten by insurance companies of nationally recognized standing providing coverage equal to or greater than the coverage under the terminated, cancelled or lapsed policies at substantially similar premiums to the premiums for the policies that are currently in full force and effect;

(xiii) increase any coverage or premiums under any directors' and officers' insurance policy or enter into any new such policy;

(xiv) adopt a plan of liquidation or any resolutions or enter into any agreement providing for the amalgamation, merger, consolidation, reorganization, liquidation, dissolution or any other extraordinary transaction in respect of Rhyolite;

(xv) other than as permitted by this Arrangement Agreement, enter into any transaction or perform any act which might interfere with or be materially inconsistent with the successful completion of the Arrangement or any other transactions contemplated by this Arrangement Agreement or which would render, or which may reasonably be expected to render, untrue or inaccurate (without giving effect to, applying or taking into consideration any materiality or Material Adverse Effect qualification already contained within such representation or warranty) in any material respect at any time prior to the Effective Time, any of Rhyolite's representations and warranties set forth in this Arrangement Agreement; and

(xvi) announce an intention, enter into any formal or informal agreement, or otherwise make a commitment to do any of the things prohibited by any of the foregoing subparagraphs.

(1) Certain Actions

Other than as permitted by this Arrangement Agreement, Rhyolite shall:

(i) not take any action or permit any action to be taken or not taken by Rhyolite, inconsistent with the provisions of this Arrangement Agreement or which would reasonably be expected to materially impede the completion of the Arrangement or any other transactions contemplated by this Arrangement Agreement; and

(ii) promptly notify HART of: (A) any Material Adverse Change or Material Adverse Effect, or any change, event, occurrence or effect that could reasonably be expected to become a Material Adverse Change or to have a Material Adverse Effect, in respect of Rhyolite; (B) any Governmental Entity or third Person making or commencing a complaint, investigation or hearing (or communications indicating that the same may be contemplated) involving any Governmental Entity, Canadian Securities Administrator, stock exchange or other Person with respect to the Arrangement or any other transactions contemplated by this Arrangement Agreement; (C) any breach by Rhyolite of any material covenant or agreement contained in this Arrangement Agreement; and (D) any event occurring subsequent to the date hereof that would render any representation or warranty of Rhyolite contained in this Arrangement Agreement, if made on or as of the date of such event or the Effective Date, to be untrue or inaccurate such that the condition set forth in Section 6.03(a) would not be satisfied.

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(m) Employment Arrangements

Rhyolite shall not, without the prior written consent of HART, which consent shall not be unreasonably withheld, enter into or modify any employment, consulting, severance, collective bargaining or similar agreement, policy or arrangement with, or grant any bonus, salary increase, option to purchase shares, pension or supplemental pension benefit, profit sharing, retirement allowance, deferred compensation, incentive compensation, severance, change of control or termination pay to, or make any loan to, any officer, director, employee or consultant of Rhyolite.

(n) Satisfaction of Conditions

Subject to the terms of this Arrangement Agreement, Rhyolite shall use commercially reasonable efforts, to the extent that the same is within its control, to take or cause to be taken all actions and do or cause to be done all things necessary, proper or advisable under all applicable Laws to complete the Arrangement and other transactions contemplated by this Arrangement Agreement, including using its commercially reasonable efforts to:

(i) obtain the approval of the Rhyolite Shareholders to the Arrangement in accordance with the provisions of the ABCA, the Interim Order and the requirements of any Canadian Securities Administrator;

(ii) obtain all consents, approvals and authorizations as are required to be obtained by Rhyolite under any applicable Law or from any Governmental Entity that would, if not obtained, materially impede the completion of the Arrangement or any other transactions contemplated by this Arrangement Agreement or have a Material Adverse Effect on Rhyolite;

(iii) make, or cooperate as necessary in the making of, all necessary filings and applications under all applicable Laws required in connection with the Arrangement or any other transactions contemplated by this Arrangement Agreement and take all reasonable action necessary to be in compliance with such Laws, including any filings, reports, documents or applications as may be reasonably required to be filed by HART;

(iv) oppose, lift or rescind any injunction or restraining order or other order or action challenging or affecting the Arrangement Agreement or any other transactions contemplated by this Arrangement Agreement or seeking to stop, or otherwise adversely affecting the ability of the Parties hereto to complete, the Arrangement or any other transactions contemplated by this Arrangement Agreement;

(v) cause the issuance of the HART Shares to be issued pursuant to the Arrangement to be exempt from the registration requirements of the 1933 Act pursuant to the Section 3(a)(10) Exemption and all applicable state securities laws in reliance upon similar exemptions;

(vi) fulfill all conditions required to be fulfilled or satisfied by Rhyolite; and

(vii) cooperate with HART in connection with the performance by it of its obligations under this Arrangement Agreement.

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(o) Access and Confirmatory Review

Upon reasonable notice, Rhyolite agrees to provide HART and its representatives, upon the request of HART, with reasonable access (without undue disruption to the conduct of the Rhyolite's business) during normal business hours to all books, records, information, corporate charters, Tax documents and files in the possession and control of Rhyolite, to all personnel of Rhyolite, in order to allow HART to conduct such investigations as HART may consider necessary or advisable for strategic planning and integration and for any other reasons reasonably relating to the Arrangement or any other transactions contemplated by the Arrangement Agreement. Nothing in the foregoing shall require Rhyolite to disclose any information that it is prohibited from disclosing pursuant to a written confidentiality agreement or confidentiality provision of an agreement with a third party. Any such investigation by HART and its representatives shall not mitigate, diminish or affect the representations and warranties of Rhyolite contained in this Arrangement Agreement or any document or certificate given pursuant hereto.

(p) Rhyolite Voting Support Agreement

Rhyolite shall use its commercially reasonable efforts to ensure that each of the directors and officers of Rhyolite, Northfield Capital Corp. and Tyrus Capital S.A.M. deliver duly executed Rhyolite Voting Support Agreements within five (5) Business Days following the date hereof;

(q) Rhyolite Lock-Up and Standstill Agreements

Rhyolite shall use its commercially reasonable efforts to cause Northfield Capital Corp. and all other Persons, that are known to Rhyolite, holding 3% or more of the issued and outstanding Rhyolite Shares to deliver duly executed Rhyolite Lock-Up and Standstill Agreements to HART on or prior to the Effective Date.

(r) Director and Officer Resignations and Releases

Rhyolite shall use its commercially reasonable efforts to cause all directors and officers of Rhyolite to deliver written resignations and mutual releases (provided that rights to indemnification shall be maintained), effective as of the Effective Time.

(s) Working Capital Certificate

On the fifth Business Day prior to the Effective Date, Rhyolite shall deliver to HART a certificate of a responsible financial officer setting forth Rhyolite's good faith calculation of its estimated net working capital as of the Effective Date (the "Working Capital Certificate"). The Company shall provide such information supporting the calculations set forth in the Working Capital Certificate as HART may reasonably require in order to ascertain that the condition set forth in Section 6.03(f) shall have been satisfied as of the Effective Time.

5.02 Covenants of HART

HART hereby covenants and agrees with Rhyolite as follows:

(a) Proceedings

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In a timely and expeditious manner, HART shall take all such actions and do all such acts and things as are specified in the Interim Order, the Plan of Arrangement and the Final Order to be taken or done by HART.

(b) Information for Rhyolite Circular

In a timely manner, HART shall provide to Rhyolite all information with respect to HART as may be reasonably requested by Rhyolite for the purposes of preparing the Rhyolite Circular or any amendment or supplement thereto. HART shall ensure that no such information will contain a misrepresentation (as defined under Applicable Securities Laws).

HART shall promptly notify Rhyolite of: (A) any Material Adverse Change or Material Adverse Effect in respect of HART, or any change, event, occurrence or effect that could reasonably be expected to become a Material Adverse Change or to have a Material Adverse Effect in respect of HART; (B) any Governmental Entity or third Person making or commencing a complaint, investigation or hearing (or communications indicating that the same may be contemplated involving any Governmental Entity, Canadian Securities Administrator, stock exchange or other Person) with respect to the Arrangement or any other transactions contemplated by this Arrangement Agreement; (C) any breach by HART of any covenant or agreement contained in this Arrangement Agreement; and (D) any event occurring subsequent to the date hereof that would render any representation or warranty of HART contained in this Arrangement Agreement, if made on or as of the date of such event or the Effective Date, to be untrue or inaccurate such that the condition set forth in Section 6.02(a) would not be satisfied.

(d) Copy of Documents

HART shall furnish promptly to Rhyolite a copy of each notice, report, schedule or other document or communication delivered, filed or received by HART in connection with this Arrangement Agreement, the Arrangement, any filings made under any applicable Laws and any dealings or communications with any Governmental Entity, Canadian Securities Administrator or any stock exchange in connection with, or in any way affecting, the Arrangement or any other transactions contemplated by this Arrangement Agreement.

(e) Usual Business

Except as expressly provided herein, HART shall, conduct business only, and not take any action except, in the Ordinary Course of Business and use commercially reasonable efforts to preserve intact its present business organization and goodwill, to preserve intact the HART Mineral Rights, to keep available the services of its officers and to maintain satisfactory relationships with Persons having business relationships with HART.

(f) Certain Actions

Other than as permitted by this Arrangement Agreement, HART shall:

(i) not take any action or permit any action to be taken or not taken by HART, inconsistent with the provisions of this Arrangement Agreement or which would

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reasonably be expected to materially impede the completion of the Arrangement or any other transactions contemplated by this Arrangement Agreement; and

(ii) promptly notify Rhyolite of: (A) any Material Adverse Change or Material Adverse Effect, or any change, event, occurrence or effect that could reasonably be expected to become a Material Adverse Change or to have a Material Adverse Effect, in respect of HART; (B) any Governmental Entity or third Person making or commencing a complaint, investigation or hearing (or communications indicating that the same may be contemplated) involving any Governmental Entity, Canadian Securities Administrator, stock exchange or other Person with respect to the Arrangement or any other transactions contemplated by this Arrangement Agreement; (C) any breach by HART of any material covenant or agreement contained in this Arrangement Agreement; and (D) any event occurring subsequent to the date hereof that would render any representation or warranty of HART contained in this Arrangement Agreement, if made on or as of the date of such event or the Effective Date, to be untrue or inaccurate such that the condition set forth in Section 6.02(a) would not be satisfied.

(g) Satisfaction of Conditions

Subject to the terms of this Arrangement Agreement, HART shall use commercially reasonable efforts, to the extent that the same is within its control, to take or cause to be taken all actions and do or cause to be done all things necessary, proper or advisable under all applicable Laws to complete the Arrangement and other transactions contemplated by this Arrangement Agreement, including using its commercially reasonable efforts to:

(i) obtain all consents, approvals and authorizations as are required to be obtained by HART or any of the HART Subsidiaries under any applicable Law or from any Governmental Entity or other Person, to complete the Arrangement and any other transactions contemplated by this Arrangement Agreement;

(ii) make all necessary filings and applications under all applicable Laws required to be made by HART and other transactions contemplated by this Arrangement Agreement;

(iii) oppose, lift or rescind any injunction or restraining order or other order or action challenging or affecting the Arrangement Agreement or any other transactions contemplated by this Arrangement Agreement or seeking to stop, or otherwise adversely affecting the ability of the Parties hereto to complete, the Arrangement or any other transactions contemplated by this Arrangement Agreement;

(iv) fulfill all conditions of this Arrangement Agreement required to be fulfilled by HART; and

(v) cooperate with Rhyolite in connection with the performance by Rhyolite of its obligations under this Arrangement Agreement.

(h) Stock Exchange Listing

HART shall use its commercially reasonable efforts following the date hereof to obtain as soon as possible and in any event prior to the Effective Date, evidence satisfactory to

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Rhyolite, acting reasonably, of the approval of the listing and posting for trading on the TSXV of the HART Shares to be issued under the Arrangement, subject only to the satisfaction of the customary listing conditions or notices of the TSXV.

ARTICLE 6

CONDITIONS

6.01 Mutual Conditions

The respective obligations of Rhyolite and HART to complete the Arrangement and any other transactions contemplated by this Arrangement Agreement are subject to the fulfillment of the following conditions at or before the Effective Time:

(a) the Interim Order shall have been granted on terms consistent with this Arrangement Agreement and otherwise in form and substance satisfactory to each of the Parties, acting reasonably, and shall not have been set aside or modified in a manner unacceptable to the Parties, acting reasonably, on appeal or otherwise;

(b) the Rhyolite Shareholder Approval shall have been obtained at the Rhyolite Meeting by Rhyolite Shareholders in accordance with applicable Laws and the Interim Order;

(c) the Final Order shall have been granted on terms consistent with this Arrangement Agreement and otherwise in form and substance satisfactory to each of the Parties, acting reasonably, and shall not have been set aside or modified in a manner unacceptable to the Parties, acting reasonably, on appeal or otherwise;

(d) there shall not be in force any Law, order or decree, and there shall not have been any action taken under any Law or by any Governmental Entity, Canadian Securities Administrator or stock exchange, that makes it illegal or otherwise restrains, enjoins or prohibits the completion of the Arrangement or any other transactions contemplated by this Arrangement Agreement;

(e) (i) the HART Shares to be issued in connection with the Arrangement will not be subject to any statutory hold or restricted period under the Applicable Securities Laws in Canada and will be freely tradable within Canada by the holders thereof, subject in each case to restrictions contained in Section 2.6(3) of National Instrument 45-102 – Resale of Securities of the Canadian Securities Administrators; and (ii) the HART Shares to be issued in connection with the Arrangement shall be exempt from registration requirements of the 1933 Act pursuant to the Section 3(a)(10) Exemption; and (iii) the HART Shares to be distributed in the United States pursuant to the Arrangement shall not be subject to resale restrictions in the United States under the 1933 Act (other than as may be prescribed by Rule 144 and Rule 145 under the 1933 Act);

(f) (i) the TSXV shall have conditionally approved the listing thereon, subject to the satisfaction of customary conditions required by such stock exchange, of the HART Shares to be issued pursuant to the Arrangement as of the Effective Date; and (ii) the TSXV shall have, if required, accepted notice for filing and provided conditional acceptance (if required) of all transactions of the Parties contemplated herein or necessary to complete the Arrangement, subject only to compliance with the usual requirements of the TSXV;

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(g) all material consents, waivers, permits, exemptions, orders and approvals of any Governmental Entity and the expiry of any mandatory waiting periods under applicable Laws required to permit the completion of the Arrangement or any other transactions contemplated by this Arrangement Agreement shall have been obtained;

(h) HART shall have completed the Concurrent Financing for minimum gross proceeds to HART of not less than $4,000,000; and

(i) this Arrangement Agreement shall not have been terminated pursuant to Article 8 hereof.

The foregoing conditions are for the mutual benefit of the Parties and may be waived by mutual consent of Rhyolite and HART in writing at any time.

6.02 Rhyolite Conditions

The obligation of Rhyolite to complete the Arrangement and any other transactions contemplated by this Arrangement Agreement is subject to the fulfillment of the following additional conditions at or before the Effective Date:

(a) the representations and warranties made by HART in this Arrangement Agreement shall be true and correct in all respects, without regard to any materiality or Material Adverse Effect qualifications, as of the Effective Date as if made on and as of such date (except for representations and warranties made as of a specified date, the accuracy of which shall be determined as of that specified date), except to the extent that the failure of such representations and warranties to be so true and correct, individually or in the aggregate, would not result in a Material Adverse Effect with respect to HART, and HART shall have provided to Rhyolite a certificate dated the Effective Date of one (1) officer of HART confirming same;

(b) from the date of this Arrangement Agreement to the Effective Date, there shall not have occurred a Material Adverse Effect with respect to HART and HART shall have provided to Rhyolite a certificate of one (1) officer of HART confirming same;

(c) HART shall have complied with or satisfied in all material respects its obligations, covenants and agreements herein and HART shall have provided to Rhyolite a certificate of one (1) officer of HART confirming same;

(d) all consents, waivers or approvals from any third party (other than any Governmental Entity) which are required for the completion by HART of the Arrangement and any other transactions contemplated by this Arrangement Agreement shall have been obtained, except for those the failure of which to obtain or the non-expiry of which would not have, or would not reasonably be expected to have, a Material Adverse Effect on HART; and

(e) the HART Board shall have adopted all necessary resolutions and all other necessary corporate actions shall have been taken by HART to permit the completion of the Arrangement and any other transactions contemplated by this Arrangement Agreement.

The foregoing conditions are for the exclusive benefit of Rhyolite and may be waived, in whole or in part, by Rhyolite in writing at any time.

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6.03 HART Conditions

The obligation of HART to complete the Arrangement and any other transactions contemplated by this Arrangement Agreement is subject to the fulfillment of the following additional conditions at or before the Effective Date:

(a) the representations and warranties made by Rhyolite in this Arrangement Agreement shall be true and correct in all respects, without regard to any materiality or Material Adverse Effect qualifications, as of the Effective Date as if made on and as of such date (except for representations and warranties made as of a specified date, the accuracy of which shall be determined as of that specified date), except to the extent that the failure of such representations and warranties to be so true and correct, individually or in the aggregate, would not result in a Material Adverse Effect with respect to Rhyolite (provided that the representations and warranties made by Rhyolite in Section 3.01(b) shall be true and correct in all respects (other than de minimis inaccuracies)), and Rhyolite shall have provided to HART a certificate dated the Effective Date of one (1) officer of Rhyolite confirming same;

(b) Rhyolite shall have complied with or satisfied in all material respects its obligations, covenants and agreements herein and Rhyolite shall have provided to HART a certificate of one (1) officer of Rhyolite confirming same;

(c) from the date of this Arrangement Agreement to the Effective Date, there shall not have occurred a Material Adverse Effect with respect to Rhyolite and Rhyolite shall have provided to HART a certificate of one (1) officer of Rhyolite confirming same;

(d) the Northfield Capital Corp., as a Rhyolite Locked-Up Shareholder, shall have delivered duly executed Rhyolite Lock-Up and Standstill Agreement to HART in accordance with Section 5.01(p);

(e) all directors and officers of Rhyolite shall have delivered written resignations and mutual releases (provided that rights to indemnification shall be maintained), effective as of the Effective Time, in form and substance satisfactory to HART, in its sole discretion;

(f) as of the Effective Time, Rhyolite shall have a net working capital of at least $6,000,000, and Rhyolite shall have provided to HART a certificate dated the Effective Date of one (1) officer of Rhyolite confirming same;

(g) Rhyolite Dissenting Shareholders holding no more than seven and one-half percent (7.5%) of the outstanding Rhyolite Shares shall have exercised the Rhyolite Dissent Rights (and not withdrawn such exercise) and HART shall have received a certificate, dated the day immediately preceding the Effective Date, of one (1) officer of Rhyolite confirming same;

(h) the Rhyolite Board shall have adopted all necessary resolutions and all other necessary corporate action shall have been taken by Rhyolite to permit the completion of the Arrangement and any other transactions contemplated by this Arrangement Agreement;

(i) all consents, waivers or approvals from any third party (other than any Governmental Entity) which are required for the completion by Rhyolite of the Arrangement and any other transactions contemplated by this Arrangement Agreement shall have been obtained,

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except for those the failure of which to obtain or the non-expiry of which would not have, or would not reasonably be expected to have, a Material Adverse Effect on Rhyolite; and

(j) the Rhyolite Board shall not have effected a Change in Rhyolite Recommendation.

The foregoing conditions are for the exclusive benefit of HART and may be waived, in whole or in part, by HART in writing at any time.

6.04 Nomination Right

(a) HART covenants and agrees that it shall, upon receipt of written notice from Rhyolite at least 10 Business Days prior to the Effective Date forthwith take all necessary steps, including increasing the size of the HART Board or causing the resignation of a director, to cause the appointment of an individual selected by the Rhyolite Board to serve on the HART Board until the next annual meeting of the HART Shareholders (the "Rhyolite Director Nominee"), and in the event that it is necessary to seek shareholder approval for the election of the Rhyolite Director Nominee, HART shall call and hold a meeting of its shareholders to consider the election of the Rhyolite Director Nominee as soon as reasonably practicable, and in any event such meeting shall be held within 180 days of HART receiving such written notice from Rhyolite.

(b) The Rhyolite Director Nominee must consent in writing to serve as a director of HART and comply with the ABCA and applicable Laws, including the completion of a personal information form and a corresponding background check required by the TSXV, for membership on the HART Board.

(c) To the extent that a HART Shareholder vote is required in order to add the Rhyolite Director Nominee to the HART Board at first instance, HART shall use commercially reasonable efforts to ensure that the Rhyolite Director Nominee is elected to the HART Board, including soliciting proxies in support of their election and taking the same actions taken by HART to ensure the election of the other nominees selected by the HART Board for election to the HART Board.

6.05 Notice and Cure Provisions

(a) Each Party shall give prompt notice to the other of the occurrence, or failure to occur, at any time from the date hereof until the earlier to occur of the termination of this Arrangement Agreement and the Effective Time of any event or state of facts which occurrence or failure would, or would be likely to:

(i) cause any of the representations or warranties of such Party contained herein to be untrue or inaccurate in any material respect on the date hereof or at the Effective Time; or

(ii) result in the failure to comply with or satisfy any obligation, covenant, condition or agreement to be complied with or satisfied by such Party hereunder prior to the Effective Time.

(b) No Party may elect not to complete the Arrangement or any other transactions contemplated by this Arrangement Agreement pursuant to the conditions set forth herein or exercise any termination right arising therefrom, unless the Party intending to rely

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thereon has delivered a written notice to the other Party promptly and in any event prior to the Effective Time specifying in reasonable detail all breaches of covenants, representations and warranties or other matters which the Party delivering such notice is asserting as the basis for the non-fulfilment of the applicable condition or the exercise of the termination right, as the case may be. If any such notice is delivered by a Party, and the other Party is proceeding diligently to cure such matter and such matter is capable of being cured, the Party delivering such notice may not terminate this Arrangement Agreement, other than pursuant to Sections 8.02(a)(iii)(A), 8.02(a)(iii)(B), 8.02(a)(iv)(B) or 8.02(a)(iii)(E), until the expiration of a period ending the earlier of: (i) fifteen (15) Business Days from the date of receipt of such notice, if such matter has not been cured by such date; and (ii) the Completion Deadline.

ARTICLE 7

NON-SOLICITATION, RIGHT TO MATCH, TERMINATION FEE AND EXPENSES

7.01 Non-Solicitation

(a) On and after the date hereof, except as otherwise provided in this Article 7, Rhyolite shall not, directly or indirectly, through any officer, director, employee, representative (including for greater certainty any financial or other advisors) or agent of Rhyolite (collectively, the "Rhyolite Representatives") or any other Person:

(i) make, solicit, assist, initiate, encourage or otherwise knowingly facilitate (including by way of furnishing information relating to Rhyolite or its assets, properties or books and records, permitting any visit to any facilities or properties of Rhyolite or entering into any form of written or oral agreement, arrangement or understanding (other than a Third Party Confidentiality Agreement permitted by Section 7.03)), any inquiries, proposals or offers regarding (or which may lead to the making or completion of) an Acquisition Proposal;

(ii) engage in any discussions or negotiations regarding, or provide any information with respect to, or otherwise co-operate in any way with, or assist or participate in, facilitate or encourage, any effort or attempt by any Person to make or complete (or which may lead to the making or completion of) any Acquisition Proposal, provided that, for greater certainty, Rhyolite may advise any Person making an unsolicited Acquisition Proposal that such Acquisition Proposal does not constitute a Superior Proposal when the Rhyolite Board has so determined;

(iii) make a Change in the Rhyolite Recommendation, unless the sole basis for Change in the Rhyolite Recommendation is a Material Adverse Effect with respect to HART; or

(iv) accept or enter into, or publicly propose to accept or enter into, any letter of intent, agreement in principle, agreement, arrangement, understanding or undertaking related to any Acquisition Proposal (other than a Third Party Confidentiality Agreement permitted by Section 7.03).

(b) Rhyolite shall, and shall cause the Rhyolite Representatives to, immediately cease and terminate any existing solicitation, discussion or negotiation with any Person (other than HART or a HART Subsidiary) with respect to any potential Acquisition Proposal (or any matter that could be expected to lead thereto), whether or not initiated by Rhyolite, any of

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the Rhyolite Representatives, and, in connection therewith, Rhyolite will immediately discontinue access to any data rooms (virtual or otherwise).

(c) Rhyolite shall not waive, release any Person from, or fail to enforce on a timely basis, any obligation under any confidentiality agreement or standstill agreement or amend any such agreement and Rhyolite confirms that it has not done any of the foregoing prior to the date thereof.

(d) Rhyolite confirms that within two Business Days after the date of this Arrangement Agreement, it shall request the return or destruction of all information provided to any Persons who have entered into a confidentiality agreement with Rhyolite relating to any potential Acquisition Proposal and shall use commercially reasonable efforts to ensure that such requests are honoured in accordance with the terms of such confidentiality agreements, and shall provide copies of such correspondence relating to same to HART. Rhyolite shall promptly advise HART, at first orally and then in writing, of any response or action (actual, anticipated, contemplated or threatened) by any such Person which could reasonably be expected to hinder, prevent or delay or otherwise adversely affect the completion of the Arrangement and any other transactions contemplated by this Arrangement Agreement.

7.02 Notification of Acquisition Proposals

(a) From and after the date of this Arrangement Agreement, Rhyolite shall promptly (and in any event within twenty-four (24) hours after it has received any proposal, inquiry, offer or request) notify HART, at first orally and then in writing, of:

(i) any proposal, inquiry, offer or request (or any amendment thereto) relating to or constituting an Acquisition Proposal; or
(ii) any request for discussions or negotiations relating to, or which could reasonably lead to, an Acquisition Proposal, and/or any request for information relating to Rhyolite or contractual or legal rights or for access to books and records or a list of the Rhyolite Shareholders of which Rhyolite or any of the Rhyolite Representatives are or become aware, or any amendments to the foregoing relating to an Acquisition Proposal or a potential Acquisition Proposal.

(b) The notice of an Acquisition Proposal or potential Acquisition Proposal shall include a description of the terms and conditions of, and the identity of the Person making, any proposal, inquiry, offer, request or communication (including any amendment thereto) that relates to or could be expected to lead to an Acquisition Proposal and shall include copies of any such proposal, inquiry, offer, request or communication or any amendment thereto. Rhyolite shall also provide such other details of the proposal, inquiry, offer, request or communication, or any amendment to the foregoing, as HART may reasonably request. Rhyolite shall keep HART promptly and fully informed of the status, including any change to the material terms, of any such proposal, inquiry, offer, request or communication or any amendment thereto, and will respond promptly to all reasonable inquiries by HART with respect thereto.

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7.03 Responding to an Acquisition Proposal

Notwithstanding Section 7.01(a), if at any time following the date of this Arrangement Agreement Rhyolite receives a bona fide written Acquisition Proposal that was not solicited in breach of Section 7.01(a), Rhyolite may:

(a) contact the Person making such Acquisition Proposal and its Representatives solely for the purpose of clarifying the terms and conditions of such Acquisition Proposal; and

(b) engage in or participate in discussions or negotiations with such Person regarding such Acquisition Proposal and may provide copies of, access to, or disclosure of, confidential information, properties, facilities, books or records of Rhyolite, if and only if, in the case of this Section 7.03(b):

(i) the Rhyolite Board first determines in good faith, after consultation with its financial advisors and outside legal counsel, that such Acquisition Proposal is or could reasonably be expected to lead to a Superior Proposal;

(ii) such Person was not restricted from making the Acquisition Proposal pursuant to an existing standstill or similar restriction with Rhyolite;

(iii) Rhyolite has been, and continues to be, in compliance in all material respects with each of its obligations under this Agreement, including Article 7;

(iv) before providing any such copies, access or disclosure,

(A) Rhyolite enters into a confidentiality and standstill agreement with such Person that contains a customary standstill provision, and any such copies, access or disclosure provided to such Person shall have been (or promptly be) provided to HART (the "Third Party Confidentiality Agreement"); and

(B) Rhyolite provides HART with a true, complete and final executed copy of the Third Party Confidentiality Agreement, and concurrently provides HART with copies of all written communications and summaries of all material oral communications with such Person regarding the Acquisition Proposal.

7.04 Right to Match

(a) If Rhyolite receives an Acquisition Proposal that constitutes a Superior Proposal prior to the approval of the Arrangement Resolution by the Rhyolite Shareholders, the Rhyolite Board may authorize Rhyolite to enter into a definitive agreement with respect to such Superior Proposal or may make a Change in Rhyolite Recommendation, if and only if:

(i) the Person making the Superior Proposal was not restricted from making such Superior Proposal pursuant to an existing standstill or similar restriction with Rhyolite or any of its Subsidiaries;

(ii) Rhyolite has been, and continues to be, in compliance in all material respects with each of its obligations under this Article 7;

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(iii) Rhyolite has delivered to HART a written notice of the determination of the Rhyolite Board that such Acquisition Proposal constitutes a Superior Proposal and of the intention of the Rhyolite Board to enter into a definitive agreement with respect to such Superior Proposal or make a Change in Rhyolite Recommendation, including a notice as to the value in financial terms that the Rhyolite Board has, in consultation with its financial advisors, determined should be ascribed to any non-cash consideration offered under the Superior Proposal (a "Superior Proposal Notice");

(iv) Rhyolite has provided HART with a copy of the proposed definitive agreement for the Superior Proposal, including all supporting materials (including any financing documents, subject to customary confidentiality provisions with respect to fee letters or similar information) in connection with such Superior Proposal;

(v) at least ten (10) Business Days (the "Matching Period") have elapsed from the date that is the later of the date on which HART received the Superior Proposal Notice and the date on which HART received a copy of the all of the materials referred to in Section 7.04(a)(iv);

(vi) during any Matching Period, HART has had the opportunity (but not the obligation), in accordance with Section Error! Reference source not found., to offer to amend this Agreement, and the Plan of Arrangement in order for such Acquisition Proposal to cease to be a Superior Proposal;

(vii) after the Matching Period, the Rhyolite Board has determined, in good faith, after consultation with its financial advisors and outside legal counsel, that such Acquisition Proposal continues to constitute a Superior Proposal (and, if applicable, compared to the terms of the Arrangement as proposed to be amended by HART under Section Error! Reference source not found.); and

(viii) prior to or concurrently with entering into such definitive agreement, Rhyolite terminates this Agreement pursuant to Section 8.02(a)(iv)(A) and pays the Rhyolite Termination Fee.

(b) During the Matching Period, or such longer period as Rhyolite may approve (in its sole discretion) in writing for such purpose: (i) HART shall have the opportunity (but not the obligation) to offer to amend this Agreement and the Plan of Arrangement; (ii) the Rhyolite Board shall, in good faith and in consultation with outside legal counsel and financial advisors, review any offer made by HART to amend the terms of this Agreement and the Arrangement in order to determine whether such proposal would, upon acceptance, result in the Acquisition Proposal previously determined to constitute a Superior Proposal ceasing to be a Superior Proposal; and (iii) Rhyolite shall, and shall cause its Representatives to, negotiate in good faith with HART to make such amendments to the terms of this Agreement and the Plan of Arrangement as would enable HART to proceed with the transactions contemplated by this Agreement on such amended terms. If, as a consequence of the foregoing, the Rhyolite Board determines that such Acquisition Proposal would cease to be a Superior Proposal, Rhyolite shall promptly so advise HART and Rhyolite and HART shall amend this Agreement to reflect such offer made by HART and shall take or cause to be taken all such actions as are necessary to give effect to the foregoing.

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(c) Each successive amendment or modification to any Acquisition Proposal that results in an increase in, or modification of, the consideration (or value of such consideration) to be received by the Rhyolite Shareholders or other material terms or conditions thereof shall constitute a new Acquisition Proposal for purposes of this Section 7.04(c), and HART shall be afforded a new ten (10) Business Day Matching Period from the later of the date on which HART received the Superior Proposal Notice and the date on which HART received all of the materials referred to in Section 7.04(a)(iv) with respect to each new Superior Proposal from Rhyolite.

(d) The Rhyolite Board shall promptly reaffirm the Rhyolite Recommendation by news release after any Acquisition Proposal that the Rhyolite Board has determined not to be a Superior Proposal is publicly announced or publicly disclosed, or the Rhyolite Board determines that a proposed amendment to the terms of this Agreement and the Arrangement as contemplated under Section Error! Reference source not found. would result in an Acquisition Proposal no longer being a Superior Proposal. Rhyolite shall provide HART and its Representatives with a reasonable opportunity to review the form and content of any such news release and shall make all reasonable amendments to such news release as requested by HART and its and its Representatives.

(e) Notwithstanding the provision by Rhyolite of a Superior Proposal Notice to HART, Rhyolite shall not postpone, cancel, or take any other steps to delay the Rhyolite Meeting without the express written consent of HART.

7.05 Permitted Disclosure

Notwithstanding anything to the contrary set forth in this Agreement (including this Article 7), nothing shall prohibit the Rhyolite Board from:

(a) making any disclosure prior to the Effective Time that is (A) expressly required under Applicable Securities Laws and (B) which the Rhyolite Board has determined in good faith, after consultation with its outside legal counsel, that the failure to make such disclosure would constitute a breach of its fiduciary duties, provided that:

(i) Rhyolite shall deliver to HART and its outside legal counsel a draft of any such disclosure at least two (2) Business Days in advance of its proposed public release,

(ii) Rhyolite shall consult in good faith with HART and its outside legal counsel regarding the form and content of such disclosure, and

(iii) Rhyolite shall give reasonable and good faith consideration to any comments provided by HART and its outside legal counsel, and shall incorporate any comments reasonably requested by HART to the extent permitted by Applicable Securities Laws; and

(b) nothing shall prohibit the Rhyolite Board from calling or holding a meeting of the Rhyolite Shareholders requisitioned by the Rhyolite Shareholders in accordance with the ABCA, provided that no such meeting shall be called, held or permitted to occur prior to the Rhyolite Meeting (or any adjournment or postponement thereof), and provided further that any such meeting shall not interfere with or delay the Rhyolite Meeting.

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7.06 Termination Fee

Except as otherwise provided herein, all fees, costs and expenses incurred by a Party in connection with this Arrangement Agreement and the Plan of Arrangement shall be paid by the Party incurring such fees, costs or expenses.

(a) If a Rhyolite Termination Fee Event occurs, Rhyolite shall pay, or cause to be paid, to HART (by wire transfer of immediately available funds) the Rhyolite Termination Fee as set forth in Section 7.06(b).

(b) For the purposes of this Arrangement Agreement, "Rhyolite Termination Fee Event" means:

(i) the termination of this Arrangement Agreement pursuant to Section 8.02(a)(iii)(A), Section 8.02(a)(iii)(D), or Section 8.02(a)(iv)(A) of this Arrangement Agreement; in which case the Rhyolite Termination Fee shall be paid to HART in readily available funds as soon as practicable and in any event within two (2) Business Days after the date on which this Arrangement Agreement is terminated (except in the case of a termination in the case of Section 8.02(a)(iv)(A), in which case the Rhyolite Termination Fee shall be paid to HART in readily available funds at the time set forth in Section 7.04(a)(viii)); and

(ii) the termination of this Arrangement Agreement pursuant to Section 8.02(a)(ii)(A), Section 8.02(a)(ii)(C), Section 8.02(a)(iii)(B) or Section 8.02(a)(iii)(C) if, in any such case, prior to the earlier of the termination of this Arrangement Agreement or the holding of the Rhyolite Meeting:

(A) an Acquisition Proposal, or the intention to make a bona fide Acquisition Proposal with respect to Rhyolite shall have been made to Rhyolite or publicly announced by any Person (other than HART or any of the HART Subsidiaries) and not withdrawn prior to the earlier of the termination of this Arrangement Agreement or the holding of the Rhyolite Meeting; and

(B) within twelve (12) months after the date of termination of this Arrangement Agreement or the holding of the Rhyolite Meeting following which the Arrangement Agreement is terminated, as applicable, an Acquisition Proposal has been (i) completed; (ii) or accepted, recommended or approved by the Rhyolite Board and subsequently completed any time thereafter,

in which case the Rhyolite Termination Fee shall be paid to HART in readily available funds as soon as practicable and in any event within two (2) Business Days after the date on which the Acquisition Proposal has been completed.

For the purposes of the foregoing, the term "Acquisition Proposal" shall have the meaning specified in Subsection 1.1 except that references to "50% or more" shall be deemed to be references to "100%".

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(c) Each of the Parties acknowledges that the agreements contained in this Section 7.06 are an integral part of the transactions contemplated in this Arrangement Agreement and that, without those agreements, the Parties would not enter into this Arrangement Agreement. Each Party acknowledges that the payment amounts set out in this Section 7.06 are payments of liquidated damages which are a genuine pre-estimate of the damages, which HART will suffer or incur as a result of the event giving rise to such payment and the resultant termination of this Arrangement Agreement and are not penalties. Rhyolite irrevocably waives any right it may have to raise as a defence that any such liquidated damages are excessive or punitive.

(d) Each Party agrees that, upon any termination of this Arrangement Agreement under circumstances where HART is entitled to the Rhyolite Termination Fee and such Rhyolite Termination Fee is paid in full, HART shall be precluded from any other remedy against Rhyolite at Law or in equity or otherwise (including an order for specific performance), and shall not seek to obtain any recovery, judgment, or damages of any kind, including consequential, indirect, or punitive damages, against Rhyolite, any of its partners, managers, members, shareholders or affiliates, or the Rhyolite Representatives in connection with this Arrangement Agreement or the Arrangement and any other transactions contemplated by this Arrangement Agreement, provided that nothing in this Section 7.06 shall: (i) relieve or limit or have the effect of relieving or limiting Rhyolite or any of the Persons referred to above in any way from any liability for damages incurred or suffered by HART; or (ii) preclude HART from obtaining other relief at Law or in equity or otherwise (including an order for specific performance), in any case where there has been an intentional or wilful breach of this Arrangement Agreement by Rhyolite.

7.07 Access to Information

(a) From the date hereof until the earlier of the Effective Time and the termination of this Arrangement Agreement, subject to compliance with applicable Laws and the terms of any existing contracts, Rhyolite shall, and shall cause the Rhyolite Representatives to, provide to HART and to the officers, employees, agents and representatives of HART such access as HART may reasonably require at all reasonable times, including for the purpose of facilitating integration business planning, to the Rhyolite Representatives and any properties, books, records, contracts, data and information as HART may reasonably request.

7.08 Confidentiality

(a) Each Recipient will treat confidentially and not disclose, and will cause each of its Representatives to treat confidentially and not disclose, other than as expressly contemplated by this Agreement, any Confidential Information of a Discloser.

(b) A Recipient may disclose Confidential Information only to those of its Representatives who need to know such Confidential Information for the purpose of implementing the transaction contemplated by this Agreement. No Recipient will use, nor permit its Representatives to use, Confidential Information for any other purpose nor in any way that is, directly or indirectly, detrimental to the applicable Discloser.

(c) If a Recipient or any of its Representatives receives a request or is legally required to disclose all or any part of the Confidential Information of a Discloser, such Recipient will (i) promptly notify the Discloser of the request or requirement, (ii) consult with the

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Discloser on the advisability of taking legally available steps to resist or narrow the request or lawfully avoid the requirement, and (iii) if requested by the Discloser, take all commercially reasonable steps to seek a protective order or other appropriate remedy. If a protective order or other remedy is not available, or if the Discloser waives compliance with the provisions of this Section Error! Reference source not found., then: (A) the Recipient receiving the request for disclosure or its Representatives, as the case may be, may disclose to the Person requiring disclosure only that portion of the Confidential Information which such Recipient is advised by written opinion of counsel is legally required to be disclosed, and (B) such Recipient will not be liable for such disclosure unless such disclosure was caused by or resulted from a previous disclosure by such Recipient or its Representatives not permitted by this Agreement.

(d) Following the termination of this Agreement in accordance with the provisions of this Agreement, each Recipient will (and will cause each of its Representatives to): (i) return promptly to the Discloser all physical copies of the Confidential Information of the Discloser, excluding Notes, then in such Recipient's possession or in the possession of its Representatives, (ii) destroy all (A) electronic copies of such Confidential Information, and (B) Notes (including electronic copies thereof, other than ordinary course archival backup) prepared by such Recipient or any of its Representatives, in a manner that ensures the same may not be retrieved or undeleted by such Recipient or any of its Representatives, and (iii) deliver to the Discloser a certificate executed by one of the Recipient's duly authorized senior officers indicating that the requirements of this Section 7.08(d) have been satisfied in full.

ARTICLE 8

TERM, TERMINATION, AMENDMENT AND WAIVER

8.01 Term

This Arrangement Agreement shall be effective from the date hereof until the earlier of the Effective Time and the termination of this Arrangement Agreement in accordance with its terms.

8.02 Termination

(a) Subject to Section 8.02(c) hereof, this Arrangement Agreement may be terminated and the Arrangement may be abandoned at any time prior to the Effective Time (notwithstanding any approval of the Arrangement Resolution by the Rhyolite Shareholders or the granting of the Final Order by the Court):

(i) by mutual written agreement of Rhyolite and HART;

(ii) by either Rhyolite or HART, if:

(A) the Effective Time shall not have occurred on or before the Completion Deadline, except that the right to terminate this Arrangement Agreement under this Section 8.02(a)(ii)(A) shall not be available to any Party whose breach of this Arrangement Agreement has been the direct or indirect cause of the failure of the Effective Time to occur by the Completion Deadline;

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(B) after the date hereof, there shall be enacted or made any applicable Law that makes completion of the Arrangement illegal or otherwise prohibits or enjoins Rhyolite or HART from completing the Arrangement; or

(C) the Arrangement Resolution shall have failed to obtain the Rhyolite Shareholder Approval at the Rhyolite Meeting (including any adjournment or postponement thereof) in accordance with the Interim Order, provided that a Party may not terminate this Agreement pursuant to this Section 8.02 if the failure to obtain the Rhyolite Shareholder Approval has been caused by, or is a result of, a breach by such Party of any of its representations or warranties or the failure of such Party to perform any of its covenants or agreements under this Agreement;

(iii) by HART, if:

(A) prior to obtaining the Rhyolite Shareholder Approval, there is a Change in Rhyolite Recommendation (unless the basis for the Change in Rhyolite Recommendation is as result of a Material Adverse Effect with respect to HART);

(B) subject to Section 6.05, any condition set forth in Section 6.01 or Section 6.03 is not satisfied or waived by the Completion Deadline or such condition is incapable of being satisfied by the Completion Deadline, provided that HART has not breached this Arrangement Agreement so as to cause any of the conditions set forth in Section 6.01 or Section 6.03 not to be satisfied;

(C) subject to Section 6.056.04, a breach of any representation or warranty or failure to perform any covenant or agreement on the part of Rhyolite set forth in this Arrangement Agreement (other than as set forth in Article 7) shall have occurred that would cause the conditions set forth in Section 6.03(a) or 6.03(b) not to be satisfied, and such conditions are incapable of being satisfied by the Completion Deadline; provided that HART has not breached this Arrangement Agreement so as to cause any of the conditions set forth in Section 6.01 or Section 6.03 not to be satisfied;

(D) Rhyolite is in material breach or in default of any of its obligations or covenants set forth in Article 7;

(E) the Rhyolite Meeting has not occurred on or before June 30, 2026 (or such later date permitted by Section 5.01(d)) except that the right to terminate this Arrangement Agreement under this Section 8.02(a)(iii)(E) shall not be available to HART where the failure to fulfill any of its obligations under this Arrangement Agreement has been the cause of, or directly resulted in, the failure of the Rhyolite Meeting to occur on or before such date; or

(F) prior to the Effective Time, there has been a Material Adverse Effect in respect of Rhyolite which is incapable of being cured by the Completion Deadline.

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(iv) by Rhyolite, if:

(A) the Rhyolite Board authorizes Rhyolite, subject to complying with the terms of this Arrangement Agreement, to accept, approve or recommend, or enter into a legally binding agreement with respect to, a Superior Proposal in accordance with Article 7; provided that concurrently with such termination, Rhyolite pays the Rhyolite Termination Fee payable pursuant to Section 7.06;

(B) subject to Section 6.05, any condition set forth in Section 6.01 or Section 6.02 is not satisfied or waived by the Completion Deadline or such condition is incapable of being satisfied by the Completion Deadline; provided that Rhyolite has not breached this Arrangement Agreement so as to cause any of the conditions set forth in Section 6.01 or Section 6.02 not to be satisfied; or

(C) subject to Section 6.05, a breach of any representation or warranty or failure to perform any covenant or agreement on the part of HART set forth in this Arrangement Agreement shall have occurred that would cause the conditions set forth in Section 6.02(a) or 6.02(b) not to be satisfied, and such conditions are incapable of being satisfied by the Completion Deadline, provided that Rhyolite has not breached this Arrangement Agreement so as to cause any of the conditions set forth in Section 6.01 or Section 6.02 not to be satisfied.

(b) The Party desiring to terminate this Arrangement Agreement pursuant to this Section 8.02 (other than pursuant to Section 8.02(a)(i)) shall give written notice of such termination to the other Party.

(c) If this Arrangement Agreement is terminated pursuant to this Section 8.02, this Arrangement Agreement shall become void and of no further force or effect without liability or ongoing obligation of any Party (or any shareholder, director, officer, employee, agent, consultant or representative of such Party) to any other Party hereto, except as otherwise expressly contemplated in this Arrangement Agreement, and provided that the provisions of this Section 8.02(c), Section 7.06, Section 9.01, 9.02, 9.03, 9.04, 9.05, 9.06, 9.08 and 9.10 shall survive any termination hereof pursuant to Section 8.02; provided further that neither the termination of this Arrangement Agreement nor anything contained in this Section 8.02 shall relieve a Party from any liability for any wilful breach by it of this Arrangement Agreement.

8.03 Amendment or Waiver

This Arrangement Agreement and the Plan of Arrangement may, at any time and from time to time before or after the holding of the Rhyolite Meeting but not later than the Effective Time, be amended or any provision thereof be waived by mutual written agreement of Rhyolite and HART, and any such amendment or waiver may, subject to the Interim Order and the Final Order and applicable Laws, without limitation:

(a) change the time for performance of any of the obligations or acts of the Parties;

(b) waive any inaccuracies or modify any representation or warranty contained herein or in any document delivered pursuant hereto;

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(c) waive compliance with or modify any of the covenants herein contained and waive or modify performance of any of the obligations of the Parties; or

(d) waive compliance with or modify any mutual conditions precedent herein contained.

Any amendment or waiver made or granted as aforesaid shall affect only the matter, and the occurrence thereof, specifically identified in the amendment or waiver and shall not extend to any other matter or occurrence.

ARTICLE 9

GENERAL

9.01 Privacy

Each Party shall comply with applicable privacy Laws in the course of collecting, using and disclosing personal information about an identifiable individual (the "Transaction Personal Information"). Neither Party shall disclose Transaction Personal Information to any Person other than to its advisors who are evaluating and advising on the Arrangement and any other transactions contemplated by this Arrangement Agreement. If HART completes the Arrangement and any other transactions contemplated by this Arrangement Agreement, HART shall not, following the Effective Date, without the consent of the individuals to whom such Transaction Personal Information relates or as permitted or required by applicable Law, use or disclose Transaction Personal Information for purposes other than those for which such Transaction Personal Information was collected by Rhyolite prior to the Effective Date and which does not relate directly to the carrying on of Rhyolite's business or to the carrying out of the purposes for which the Arrangement and any other transactions contemplated by this Arrangement Agreement were implemented.

Each Party shall protect and safeguard the Transaction Personal Information against unauthorized collection, use or disclosure. Each Party shall cause its advisors to observe the terms of this Section 9.01 and to protect and safeguard Transaction Personal Information in their possession. If this Arrangement Agreement shall be terminated, each Party shall promptly deliver to other Party all Transaction Personal Information relating to such other Party in its possession or in the possession of any of its advisors, including all copies, reproductions, summaries or extracts thereof.

9.02 Notices

Any notice, consent, waiver, direction or other communication required or permitted to be given under this Arrangement Agreement by a Party shall be in writing and shall be delivered by hand to the Party to which the notice is to be given at the following address or sent by email to the following numbers or email addresses or to such other address as shall be specified by a Party by like notice. Any notice, consent, waiver, direction or other communication aforesaid shall, if delivered, be deemed to have been given and received on the date on which it was delivered to the address provided herein (if a Business Day or, if not, then the next succeeding Business Day) and if sent by email be deemed to have been given and received at the time of receipt (if a Business Day or, if not, then the next succeeding Business Day) unless actually received after 4:00 p.m. (Toronto time) at the point of delivery in which case it shall be deemed to have been given and received on the next Business Day. The address for service of each of the Parties hereto shall be as follows:

(a) if to Rhyolite:

Rhyolite Resources Ltd.
Three Bentall Centre

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Suite 1703, 595 Burrard Street
Vancouver, British Columbia V7X 1J1

Attention: Richard A. Graham, Chief Executive Officer
Email: [Redacted – Personal Information]

with a copy (which shall not constitute notice) to:

Cassels Brock & Blackwell LLP
Bay Adelaide Centre – North Tower
3200 – 40 Temperance Street
Toronto, Ontario M5H 0B4

Attention: Jay Goldman, Partner
Email: [Redacted – Personal Information]

(b) if to HART:

Gold Hart Copper Corp.
3400 One First Canadian Place, P.O. Box 130
Toronto, Ontario M5X 1A4

Attention: Isaac Maresky, Chief Executive Officer and Director
Email: [Redacted – Personal Information]

with a copy (which shall not constitute notice) to:

Bennett Jones LLP
3400 One First Canadian Place, P.O. Box 130
Toronto, Ontario M5X 1A4

Attention: Aaron Sonshine
Email: [Redacted – Personal Information]

9.03 Remedies

The Parties acknowledge and agree that an award of money damages may be inadequate for any breach of this Arrangement Agreement by any Party or its officers, directors, employees, representatives, agents or advisors (including for greater certainty any financial or other advisors) and that such breach may cause the non-breaching Party irreparable harm. Accordingly, the Parties agree that, in the event of any such breach or threatened breach of this Arrangement Agreement by one of the Parties or any of its officers, directors, employees, representatives, agents or advisors (including for greater certainty any financial or other advisors), each other Party will be entitled, without the requirement of posting a bond or other security, to equitable relief, including injunctive relief and specific performance. Such remedies will not be the exclusive remedies for any breach of this Arrangement Agreement but will be in addition to all other remedies available hereunder or at Law or in equity to each of the Parties.

9.04 Expenses

(a) Except as otherwise provided in this Arrangement, the Parties agree that all expenses incurred in connection with this Arrangement Agreement and the Arrangement and any

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other transactions contemplated by this Arrangement Agreement, the Rhyolite Meeting, the preparation and mailing of the Rhyolite Circular, including legal and accounting fees, printing costs, financial advisor fees and all disbursements by advisors, shall be paid by the Party incurring such expense and that nothing in this Arrangement Agreement shall be construed so as to prevent the payment of such expenses.

(b) In addition to the rights of HART under Section 7.06(b)7.06(b), if this Arrangement Agreement is terminated by HART pursuant to Section 8.02(a)(iii)(B)8.02(a)(iii)(B) (in circumstances where Rhyolite fails to obtain Rhyolite Shareholder Approval as required by Section 6.01(b)) and no Rhyolite Termination Fee is payable, then Rhyolite shall, within five (5) Business Days of such termination, pay or cause to be paid to HART by wire transfer in immediately available funds an amount equal to $125,000 as reimbursement to HART for its expenses incurred in connection with the Arrangement. Under no circumstances will Rhyolite be obligated to pay a Rhyolite Termination Fee if it has already paid the $125,000 to HART pursuant to the foregoing.

9.05 Time of the Essence

Time shall be of the essence in this Arrangement Agreement.

9.06 Entire Agreement

This Arrangement Agreement, together with the agreements and other documents herein or therein referred to, constitute the entire agreement and understanding between the Parties pertaining to the subject matter hereof and supersede all prior agreements, understandings, negotiations and discussions, whether oral or written, between the Parties with respect to the subject matter hereof, including, without limitation, the Letter Agreement. There are no representations, warranties, covenants or conditions with respect to the subject matter hereof.

9.07 Further Assurances

Each Party shall, from time to time, and at all times hereafter, at the request of the other Party, but without further consideration, do, or cause to be done, all such other acts and execute and deliver, or cause to be executed and delivered, all such further agreements, transfers, assurances, instruments or documents as shall be reasonably required in order to fully perform and carry out the terms and intent hereof including the Plan of Arrangement.

9.08 Governing Law

This Arrangement Agreement shall be governed by, and be construed in accordance with, the laws of the Province of Alberta and the federal laws of Canada applicable therein but the reference to such laws shall not, by conflict of laws rules or otherwise, require the application of the Law of any jurisdiction other than the Province of Alberta. Each of the Parties hereby irrevocably attorns to the exclusive jurisdiction of the Courts of the Province of Alberta in respect of all matters arising under and in relation to this Arrangement Agreement and waives any defences to the maintenance of an action in the Courts of the Province of Alberta.

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9.09 Execution in Counterparts

This Arrangement Agreement may be executed in one or more counterparts, each of which shall conclusively be deemed to be an original and all such counterparts collectively shall be conclusively deemed to be one and the same. Delivery of an executed counterpart of the signature page to this Arrangement Agreement by electronic means shall be effective as delivery of a manually executed counterpart of this Arrangement Agreement, and any Party delivering an executed counterpart of the signature page to this Arrangement Agreement by facsimile or other electronic means to the other Party shall thereafter also promptly deliver a manually executed original counterpart of this Arrangement Agreement to such other Party, but the failure to deliver such manually executed original counterpart shall not affect the validity, enforceability or binding effect of this Arrangement Agreement.

9.10 No Personal Liability

(a) No director or officer of Rhyolite (in such capacity) shall have any personal liability whatsoever to HART under this Arrangement Agreement or any other document delivered by or on behalf of Rhyolite in connection with the Arrangement by or any other transactions contemplated by this Arrangement Agreement.

(b) No director or officer of HART (in such capacity) shall have any personal liability whatsoever to Rhyolite under this Arrangement Agreement or any other document delivered by or on behalf of HART in connection with the Arrangement or any other transactions contemplated by this Arrangement Agreement.

9.11 Enurement and Assignment

HART may assign all or any part of its rights under this Arrangement Agreement to, and its obligations under this Arrangement Agreement (other than its obligation to issue HART Shares as consideration under the Arrangement) may be assumed by, a HART Subsidiary, provided that if such assignment and/or assumption takes place, HART shall continue to be liable jointly and severally with such HART Subsidiary for all of HART's obligations hereunder. For greater certainty, any assignment to a HART Subsidiary shall not relieve HART of its obligation to cause the issuance and delivery of the HART Shares to the Rhyolite Shareholders in accordance with the Arrangement. This Arrangement Agreement shall be binding on, and shall enure to the benefit of, the Parties and their respective successors and permitted assigns. No third party shall have any rights hereunder, other than as set forth in Section Error! Reference source not found.. Except as expressly permitted by the terms thereof, neither this Arrangement Agreement nor any of the rights, interests or obligations hereunder may be assigned by either of the Parties without the prior written consent of the other Party.

IN WITNESS WHEREOF the parties hereto have executed this Arrangement Agreement as of the date first above written.

RHYOLITE RESOURCES LTD.

Per: (signed) “Michael Leskovec”
Name: Michael Leskovec
Title: Director

GOLD HART COPPER CORP.

Per: (signed) “Isaac Maresky”
Name: Isaac Maresky
Title: Chief Executive Officer, Director

[Signature Page to the Arrangement Agreement]

SCHEDULE "A"
PLAN OF ARRANGEMENT UNDER SECTION 193 OF PART 15
OF THE BUSINESS CORPORATIONS ACT (ALBERTA)

ARTICLE 1
DEFINITIONS AND INTERPRETATION

1.01 Definitions

In this Plan of Arrangement, unless the context otherwise requires, the following words and terms with the initial letter or letters thereof capitalized shall have the meanings ascribed to them below:

"ABCA" means the Business Corporations Act (Alberta);

"Arrangement" means an arrangement under the provisions of Section 193 of Part 15 of the ABCA on the terms and conditions set forth in this Plan of Arrangement, subject to any amendment or supplement thereto made in accordance therewith, herewith or made at the direction of the Court in the Final Order with the consent of HART and Rhyolite, acting reasonably;

"Arrangement Agreement" means the arrangement agreement dated as of April 6, 2026 between HART and Rhyolite, together with the schedules attached thereto, as amended, amended and restated, or supplemented from time to time;

"Arrangement Consideration" means one HART Share for every 2.6 Rhyolite Shares (the "Arrangement Consideration Factor");

"Arrangement Resolution" means the special resolution of the Rhyolite Shareholders approving the Arrangement, the Plan of Arrangement and the Arrangement Agreement, substantially in the form set out in Schedule "B" to the Arrangement Agreement;

"Business Day" means any day, other than a Saturday, a Sunday or a statutory holiday in Vancouver, British Columbia, Calgary, Alberta or Toronto, Ontario;

"Court" means the Court of King's Bench of Alberta;

"Depository" means the depositary agent, to be appointed upon mutual agreement of the Parties (each acting reasonably) for the purpose of, among other things, exchanging the Rhyolite Shares for HART Shares in connection with the Arrangement;

"Effective Date" means the date the Arrangement completes, as determined in accordance with the Arrangement Agreement;

"Effective Time" means 8:00 a.m. (Toronto time) on the Effective Date, or such other time as the Parties may agree to in writing before the Effective Date;

"Final Order" means the final order of the Court in form acceptable to HART and Rhyolite, each acting reasonably, approving the Arrangement, as such order may be amended, supplemented or varied by the Court with the consent of the Parties at any time prior to the Effective Date or, if appealed, then unless such appeal is withdrawn or denied, as affirmed or as amended on appeal;

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"Former Rhyolite Shareholders" means, at and following the Effective Time, the holders of Rhyolite Shares immediately prior to the Effective Time and, for greater certainty, includes without limitation, Rhyolite Dissenting Shareholders;

"Governmental Entity" means;

"HART" means Gold Hart Copper Corp., a corporation existing under the laws of the Province of British Columbia;

"HART Shares" means common shares in the capital of HART;

"Interim Order" means the interim order of the Court pursuant to the ABCA, made in connection with the Arrangement, as such order may be amended, supplemented or varied by the Court with the consent of HART and Rhyolite, each acting reasonably;

"Letter of Transmittal" means the letter of transmittal sent by Rhyolite to the Rhyolite Shareholders for use in connection with the Arrangement, providing for the delivery of certificates representing Rhyolite Shares to the Depositary;

"Person" means an individual, partnership, association, body corporate, joint venture, business organization, trustee, executor, administrative legal representative, Governmental Entity or any other entity, whether or not having legal status;

"Plan of Arrangement" means this plan of arrangement and any amendments or variations made in accordance with the Arrangement Agreement or this Plan of Arrangement or made at the direction of the Court in the Final Order with the prior written consent of HART and Rhyolite, each acting reasonably;

"Rhyolite" means Rhyolite Resources Ltd., a corporation existing under the ABCA;

"Rhyolite Dissent Procedures" means the procedures set out herein to be taken by a Rhyolite Shareholder in exercising Rhyolite Dissent Rights;

"Rhyolite Dissent Rights" means the rights of dissent in respect of the Arrangement as contemplated in this Plan of Arrangement;

"Rhyolite Dissenting Shareholders" means registered Rhyolite Shareholders who have duly and validly exercised their Rhyolite Dissent Rights in strict compliance with the Rhyolite Dissent Procedures and whose Rhyolite Dissent Rights have not terminated;

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"Rhyolite Meeting" means the annual and special meeting, including any adjournments or postponements thereof, of the Rhyolite Shareholders to be held, among other things, to consider and, if deemed advisable, to approve the Arrangement Resolution;

"Rhyolite Shareholders" means, at any time, the holders of Rhyolite Shares;

"Rhyolite Shares" means common shares in the capital of Rhyolite;

"Tax Act" means the Income Tax Act (Canada); and

"TSXV" means the TSX Venture Exchange.

Words and phrases used herein that are defined in the Arrangement Agreement and not defined herein shall have the same meaning herein as in the Arrangement Agreement, unless the context otherwise requires. Words and phrases used herein that are defined in the ABCA and not defined herein or in the Arrangement Agreement shall have the same meaning herein as in the ABCA, unless the context otherwise requires.

1.02 Interpretation Not Affected By Headings

The division of this Plan of Arrangement into articles, sections, subsections, paragraphs and subparagraphs and the insertion of headings herein are for convenience of reference only and shall not affect in any way the meaning or interpretation of this Plan of Arrangement. The terms "this Plan of Arrangement", "hereof", "herein", "hereto", "hereunder" and similar expressions refer to this Plan of Arrangement and not to any particular article, section or other portion thereof and include any instrument supplementary or ancillary hereto.

1.03 References to Articles, Sections, Etc.

Unless otherwise indicated, references in this Plan of Arrangement to any article, section, subsection, paragraph, subparagraph or portion thereof are a reference to the applicable article, section, subsection, paragraph, subparagraph or portion thereof in this Plan of Arrangement.

1.04 Number and Gender

In this Plan of Arrangement, unless the context otherwise requires, words importing the singular shall include the plural and vice versa, words importing the use of either gender shall include both genders and neuter.

1.05 Date for Any Action

If the date on which any action is required to be taken hereunder by any Party is not a Business Day, such action shall be required to be taken on the next succeeding day that is a Business Day.

1.06 Statutory References

Any reference in this Plan of Arrangement to a statute includes all regulations and rules made thereunder, all amendments to such statute or regulation in force from time to time and any statute or regulation that supplements or supersedes such statute or regulation.

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1.07 Currency

Unless otherwise stated, all references in this Plan of Arrangement to amounts of money are expressed in lawful money of Canada, and "$" refers to Canadian dollars.

ARTICLE 2 ARRANGEMENT AGREEMENT

2.01 Arrangement Agreement

This Plan of Arrangement is made pursuant to, and is subject to the provisions of, the Arrangement Agreement, except in respect of the sequence of the steps comprising the Arrangement which shall occur in the order set forth herein. This Plan of Arrangement constitutes an arrangement as referred to in Section 193 of Part 15 of the ABCA.

ARTICLE 3 ARRANGEMENT

3.01 Arrangement

Commencing at the Effective Time, the following events or transactions shall occur and shall be deemed to occur in the following sequence without any further act or formality:

(a) each Rhyolite Share held by a Rhyolite Dissenting Shareholder shall be deemed to be transferred by the holder thereof, without any further act or formality on its part, free and clear of all liens, claims and encumbrances, to HART, in consideration for a claim against HART in an amount determined and payable in accordance with Article 4, and the name of such holder will be removed from the central securities register as a holder of Rhyolite Shares and HART shall be recorded as the registered holder of the Rhyolite Shares so transferred and shall be deemed to be the legal owner of such Rhyolite Shares;

(b) each Rhyolite Share outstanding immediately prior to the Effective Time held by a Rhyolite Shareholder (other than any Rhyolite Dissenting Shareholder) shall be transferred by the holder thereof to HART in exchange for the Arrangement Consideration, and HART shall be deemed to be the legal and beneficial owner thereof, free and clear of any liens, claims or encumbrances, subject to Article 5;

and in each case HART shall be deemed to be the legal and beneficial owner thereof, free and clear of any liens, claims or encumbrances, subject to Article 5;

3.02 Post-Effective Time Procedures

(a) Following the receipt of the Final Order and no later than one (1) Business Day before the Effective Date, HART shall deliver or arrange to be delivered to the Depositary certificates representing the requisite HART Shares required to be issued to Former Rhyolite Shareholders in accordance with the provisions of 3.01, which certificates shall be held by the Depositary as agent and nominee for Former Rhyolite Shareholders for distribution to such Former Rhyolite Shareholders in accordance with the provisions of Article 5.

(b) Subject to the provisions of Article 5, and upon the return of a properly completed Letter of Transmittal by a registered Former Rhyolite Shareholder, together with certificates (if

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any) representing Rhyolite Shares and such other documents as the Depositary may require, the Former Rhyolite Shareholder shall be entitled to receive delivery of certificates (or electronic evidence of issue) representing the Rhyolite Shares to which it is entitled pursuant to 3.01(b).

3.03 No Fractional HART Shares

No fractional HART Shares shall be issued to Former Rhyolite Shareholders in connection with this Plan of Arrangement. The total number of HART Shares to be issued to any Former Rhyolite Shareholder shall, without additional compensation, in each case be rounded down to the nearest whole HART Share in the event that such Former Rhyolite Shareholder would otherwise be entitled to a fractional HART Share.

3.04 Transfers Free and Clear

Any transfer of securities pursuant to this Plan of Arrangement shall be free and clear of all liens, claims or encumbrances.

3.05 Binding Effect

This Plan of Arrangement will become effective at, and be binding at and after, the Effective Time on: (i) Rhyolite; (ii) HART; and (iii) Former Rhyolite Shareholders.

ARTICLE 4

DISSENT PROCEDURES

4.01 Rights of Dissent

Pursuant to the Interim Order, a Rhyolite Dissenting Shareholder may exercise the Rhyolite Dissent Rights with respect to the Rhyolite Shares held by such holder in connection with the Arrangement pursuant to and in the manner set forth in Section 191 of the ABCA, as modified by the Interim Order and this Section 4.01; provided that, notwithstanding subsection 191(5) of the ABCA, the written objection to the Arrangement Resolution must be received by Rhyolite not later than 5:00 p.m. (Toronto time) two (2) Business Days immediately preceding the date of the Rhyolite Meeting (as may be adjourned or postponed from time to time).

Each Rhyolite Dissenting Shareholder who is:

(i) ultimately entitled to be paid fair value for such holder's Rhyolite Shares: (A) shall be deemed not to have participated in the transactions in Article 3 (other than Section 3.01(a)); (B) shall be entitled to be paid the fair value of such Rhyolite Shares by HART (with funds of HART not directly or indirectly provided by Rhyolite), which fair value shall be determined as of the close of business on the Business Day immediately before the Arrangement Resolution was adopted; and (C) shall not be entitled to any other payment or consideration, including any payment that would be payable under the Arrangement had such holder not exercised their Rhyolite Dissent Rights in respect of such Rhyolite Shares; or

(ii) ultimately not entitled, for any reason, to be paid fair value for such Rhyolite Shares shall be deemed to have participated in the Arrangement on the same basis as a Rhyolite Shareholder who was not a Rhyolite Dissenting Shareholder.

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4.02 Recognition of Dissenting Holders

(a) In no circumstances shall the Parties or any other Person be required to recognize a Person exercising Rhyolite Dissent Rights unless such Person is the registered holder of those Rhyolite Shares in respect of which such Rhyolite Dissent Rights are sought to be exercised.

(b) For greater certainty, in no case shall the Parties or any other Person be required to recognize Rhyolite Dissenting Shareholders as holders of Rhyolite Shares in respect of which Rhyolite Dissent Rights have been validly exercised after the completion of the transfer of such Rhyolite Shares under Section 3.01(a), and the names of such Rhyolite Dissenting Shareholders shall be removed from the register of holders of the Rhyolite Shares in respect of which Rhyolite Dissent Rights have been validly exercised at the same time as the event described in Section 3.01(a) occurs. In addition to any other restrictions set forth in the ABCA, none of the Rhyolite Shareholders who vote or have instructed a proxyholder to vote their Rhyolite Shares in favour of the Arrangement Resolution shall be entitled to exercise their Rhyolite Dissent Rights in respect of such Rhyolite Shares.

ARTICLE 5 DELIVERY OF HART SHARES

5.01 Delivery of HART Shares

(a) Upon surrender to the Depositary for cancellation of a certificate (if any) which immediately prior to the Effective Time represented one (1) or more outstanding Rhyolite Shares which were exchanged for HART Shares, together with such other documents and instruments as would have been required to effect the transfer of the Rhyolite Shares formerly represented by such certificate (if any) under the ABCA and the articles of Rhyolite and such additional documents and instruments as the Depositary may reasonably require, the holder of such surrendered certificate shall be entitled to receive in exchange therefor, and the Depositary shall deliver to such holder following the Effective Time, one or more certificates (or electronic evidence of issue) representing the HART Shares which such holder is entitled to receive in accordance with 3.01(b).

(b) After the Effective Time and until surrendered for cancellation as contemplated by 5.01(a), each certificate which immediately prior to the Effective Time represented one or more Rhyolite Shares shall be deemed at all times to represent only the right to receive in exchange therefor the entitlements which the holder of such certificate is entitled to receive in accordance with 3.01(b).

5.02 Lost Certificates

In the event that any certificate which immediately prior to the Effective Time represented one (1) or more outstanding Rhyolite Shares which were exchanged or transferred in accordance with 3.01 shall have been lost, stolen or destroyed, upon the making of an affidavit of that fact by the Person claiming such certificate to be lost, stolen or destroyed, the Depositary shall deliver in exchange for such lost, stolen or destroyed certificate, the consideration which such Person is entitled to receive in accordance with 3.01; provided that, as a condition precedent to any such delivery by the Depositary, such Person shall have provided a bond satisfactory to HART and the Depositary in such amount as HART and the Depositary may direct, or otherwise indemnified HART and the Depositary in a manner satisfactory to HART and the Depositary, against any claim that may be made against HART and the Depositary with respect to the

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certificate alleged to have been lost, stolen or destroyed and shall otherwise have taken such actions as may be required by the articles of Rhyolite.

5.03 Distributions with Respect to Unsurrendered Certificates

No dividend or other distribution declared or made after the Effective Time with respect to HART Shares with a record date after the Effective Time shall be delivered to the holder of any unsurrendered certificate which, immediately prior to the Effective Time, represented outstanding Rhyolite Shares unless and until the holder of such certificate shall have complied with the provisions of 5.01 or 5.02. Subject to applicable laws and to 5.04, at the time of such compliance, there shall, in addition to the delivery of a certificate representing the HART Shares to which such holder is thereby entitled, be delivered to such holder, without interest, the amount of the dividend or other distribution with a record date after the Effective Time theretofoe paid with respect to such HART Shares.

5.04 Withholding Rights

HART, Rhyolite and the Depositary shall be entitled to deduct or withhold from any consideration payable or otherwise deliverable to any Person hereunder, and from all dividends or other distributions otherwise payable to any Former Rhyolite Shareholder, such amounts as HART, Rhyolite or the Depositary is required to deduct or withhold with respect to such payment under the Tax Act, the United States Internal Revenue Code of 1986 or any provision of any applicable federal, provincial, state, local or foreign Tax Laws. To the extent that amounts are so deducted or withheld, such deducted or withheld amounts shall be treated for all purposes hereof as having been paid to the relevant Person in respect of which such deduction or withholding was made, provided that such deducted or withheld amounts are remitted to the appropriate Governmental Entity. Each of Hart, Rhyolite or the Depositary is hereby authorized to sell or otherwise dispose of such portion of the Arrangement Consideration as is necessary to provide sufficient funds to HART, Rhyolite or the Depositary, as the case may be, to enable it to comply with all deduction or withholding requirements applicable to it, and HART, Rhyolite or the Depositary, as applicable, shall notify such Person and remit to such Person any unapplied balance of the net proceeds of such sale. None of Rhyolite, HART or the Depositary shall be liable for any loss arising out of any such sale.

5.05 Limitation and Proscription

To the extent that a Former Rhyolite Shareholder shall not have complied with the provisions of 5.01 or 5.02 on or before the date which is six (6) years after the Effective Date (the "Final Proscription Date"), then:

(a) any HART Shares which such Former Rhyolite Shareholder was entitled to receive shall be automatically cancelled without any repayment of capital in respect thereof and the certificates representing such HART Shares shall be delivered to HART by the Depositary for cancellation and shall be cancelled by HART, and the interest of the Former Rhyolite Shareholder in such HART Shares shall be terminated as of such Final Proscription Date; and

(b) any dividends or distributions which such Former Rhyolite Shareholder was entitled to receive under 5.03 shall be delivered by the Depositary to HART and such dividends or distributions shall be deemed to be owned by HART, and the interest of the Former Rhyolite Shareholder in such dividends or distributions shall be terminated as of such Final Proscription Date.

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5.06 U.S. Securities Laws Exemption

Notwithstanding any provision herein to the contrary, the Parties agree that the Plan of Arrangement will be carried out with the intention that all HART Shares to be issued in connection with the Arrangement shall be exempt from registration requirements of the 1933 Act pursuant to the Section 3(a)(10) Exemption, and the HART Shares to be distributed in the United States pursuant to the Arrangement shall not be subject to resale restrictions in the United States under the 1933 Act (other than as may be prescribed by Rule 144 and Rule 145 under the 1933 Act).

ARTICLE 6 AMENDMENTS

6.01 Amendments to Plan of Arrangement

(a) The Parties reserve the right to amend, modify or supplement this Plan of Arrangement at any time and from time to time, provided that each such amendment, modification or supplement must be: (i) set out in writing; (ii) agreed to in writing by the Parties; (iii) filed with the Court and, if made following the Rhyolite Meeting, approved by the Court; and (iv) communicated to Former Rhyolite Shareholders if and as required by the Court.

(b) Any amendment, modification or supplement to this Plan of Arrangement may be proposed by Rhyolite at any time prior to the Rhyolite Meeting, provided that HART shall have consented thereto in writing, with or without any other prior notice or communication, and, if so proposed and accepted by the Persons voting at the Rhyolite Meeting (other than as may be required under the Interim Order), shall become part of this Plan of Arrangement for all purposes.

(c) Any amendment, modification or supplement to this Plan of Arrangement that is approved by the Court following the Rhyolite Meeting shall be effective only if: (i) it is consented to in writing by each of the Parties; and (ii) if required by the Court, it is consented to by holders of the Rhyolite Shares, voting in the manner directed by the Court.

(d) Any amendment, modification or supplement to this Plan of Arrangement may be made following the Effective Time but shall only be effective if it is consented to by each of the Parties, provided that such amendment, modification or supplement concerns a matter which, in the reasonable opinion of the Parties, is of an administrative nature required to better give effect to the implementation of this Plan of Arrangement and is not adverse to the financial or economic interests of the Parties or any Former Rhyolite Shareholder.

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ARTICLE 7

FURTHER ASSURANCES

7.01 Further Assurances

Notwithstanding that the transactions and events set out herein shall occur and be deemed to occur in the order set out in this Plan of Arrangement without any further act or formality, each Party shall, from time to time, and at all times hereafter, at the request of the other of them, but without further consideration, do, or cause to be done, all such other acts and execute and deliver, or cause to be executed and delivered, all such further agreements, transfers, assurances, instruments or documents as shall be reasonably required in order to fully perform and carry out the terms and intent thereof.

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SCHEDULE "B"

FORM OF ARRANGEMENT RESOLUTION

BE IT RESOLVED BY SPECIAL RESOLUTION THAT:

The arrangement (as it may be modified or amended, the "Arrangement") under Section 193 of Part 15 of the Business Corporations Act (Alberta) (the "ABCA") of Rhyolite Resources Ltd. ("Rhyolite"), pursuant to the arrangement agreement (the "Arrangement Agreement") between Rhyolite and Gold Hart Copper Corp. ("HART") dated April 6, 2026, all as more particularly described and set forth in the management information circular (the "Circular") accompanied by the notice of the meeting, is hereby authorized, approved and adopted.
The plan of arrangement, as it has been or may be amended in accordance with the Arrangement Agreement and its terms (the "Plan of Arrangement"), involving Rhyolite and implementing the Arrangement, the full text of which is set out in Appendix A to the Arrangement Agreement, is hereby authorized, approved, and adopted.
The Arrangement Agreement and related transactions, the actions of the directors of Rhyolite in approving the Arrangement and the actions of the officers of Rhyolite in executing and delivering the Arrangement Agreement and any amendments thereto are hereby ratified and approved.
Notwithstanding that this resolution has been passed (and the Arrangement adopted) by the shareholders of Rhyolite or that the Arrangement has been approved by the Court of the King's Bench of Alberta (the "Court"), the directors of Rhyolite are hereby authorized and empowered, at their discretion, without further notice to, or approval of, the shareholders of Rhyolite: (a) to amend the Arrangement Agreement or the Plan of Arrangement to the extent permitted by the Arrangement Agreement or the Plan of Arrangement; or (b) subject to the terms of the Arrangement Agreement, not to proceed with the Arrangement.
Any officer or director of Rhyolite is hereby authorized and directed for and on behalf of Rhyolite to make an application to the Court for an order approving the Arrangement and to execute, under the corporate seal of Rhyolite or otherwise, and deliver such documents as are necessary or desirable to the Registrar under the ABCA to give effect to the Arrangement and Plan of Arrangement in accordance with the Arrangement Agreement, such determination to be conclusively evidenced by the execution and delivery of documents.
Any officer or director of Rhyolite is hereby authorized and directed for and on behalf of Rhyolite to execute and deliver, whether under corporate seal of Rhyolite or not, all such agreements, forms waivers, notices, certificates, confirmations and other documents and instruments and to do or cause to be done all such other acts and things as in the opinion of such officer or director may be necessary, desirable or useful for the purpose of giving effect to these resolutions, the Arrangement Agreement and the completion of the Plan of Arrangement in accordance with the terms of the Arrangement Agreement, including:

(a) all actions required to be taken by or on behalf of Rhyolite, and all necessary filings and obtaining the necessary approvals, consents and acceptances of appropriate regulatory authorities; and

(b) the signing of the certificates, consents and other documents or declarations required under the Arrangement Agreement or otherwise to be entered into by Rhyolite;

B-2 -

such determination to be conclusively evidenced by the execution and delivery of such document, agreement or instrument or the doing of any such act or thing.

AI assistant

Rhyolite Resources Ltd. — M&A Activity 2026

45883_rns_2026-04-16_19cd22b5-ab69-43a3-a92b-99fdc0deaf02.pdf

ARRANGEMENT AGREEMENT

ARRANGEMENT AGREEMENT

BETWEEN:

RECITALS:

ARTICLE 1

DEFINITIONS, INTERPRETATION AND SCHEDULES

1.01 Definitions

1.04 Number and Gender

1.05 Date for Any Action

1.06 Statutory References

1.07 Currency

1.08 Invalidity of Provisions

1.09 Accounting Matters

1.10 Knowledge

1.11 Schedules

ARTICLE 2

2.01 Arrangement

2.02 Court Proceedings

2.03 Effecting the Arrangement

2.04 Consultation

2.05 U.S. Securities Law Matters

2.06 Closing

2.07 Adjustments for Dividends, Distributions or other Corporate Events

2.08 Withholding

2.09 Share for Share Exchange

ARTICLE 3

3.01 Representations and Warranties of Rhyolite

(a) Organization

(b) Capitalization

ARTICLE 4

4.01 Representations and Warranties of HART

(a) Organization

(b) Capitalization

4.02 Survival of Representations and Warranties

ARTICLE 5 COVENANTS

5.01 Covenants of Rhyolite

(a) Interim Order

(b) The Rhyolite Meeting

ARTICLE 6

CONDITIONS

6.01 Mutual Conditions

6.02 Rhyolite Conditions

6.03 HART Conditions

6.04 Nomination Right

6.05 Notice and Cure Provisions

ARTICLE 7

7.01 Non-Solicitation

7.02 Notification of Acquisition Proposals

7.03 Responding to an Acquisition Proposal

7.04 Right to Match

7.05 Permitted Disclosure

7.06 Termination Fee

7.07 Access to Information

7.08 Confidentiality

ARTICLE 8

8.01 Term

8.02 Termination

8.03 Amendment or Waiver

ARTICLE 9

9.01 Privacy

9.02 Notices

9.03 Remedies

9.04 Expenses

9.05 Time of the Essence

9.06 Entire Agreement

9.07 Further Assurances

9.08 Governing Law

9.09 Execution in Counterparts

9.10 No Personal Liability

9.11 Enurement and Assignment

RHYOLITE RESOURCES LTD.

GOLD HART COPPER CORP.

1.02 Interpretation Not Affected By Headings

1.03 References to Articles, Sections, Etc.

1.04 Number and Gender

1.05 Date for Any Action

1.06 Statutory References

Rhyolite Resources Ltd. M&A Activity 2026