Ero Copper Corp. — Capital/Financing Update 2021

Mar 15, 2021

Execution Version

FIFTH AMENDING AGREEMENT AND CONSENT

THIS AGREEMENT is made as of May 29, 2020

AMONG:

ERO COPPER CORP.

as Borrower

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THE BANK OF NOVA SCOTIA

as Administrative Agent

• and -

THE BANK OF NOVA SCOTIA and BANK OF MONTREAL

as Lenders

BACKGROUND

WHEREAS pursuant to an amended and restated credit agreement made as of December 13, 2018 (as amended by a first amending agreement dated as of January 21, 2019, a second amending agreement dated as of March 12, 2019, a third amending agreement dated as of June 26, 2019 and a fourth amending agreement dated as of March 31, 2020, the “ Credit Agreement ”) among the parties hereto, the Lenders agreed to make certain credit facilities available to the Borrower for the purposes set forth therein.

AND WHEREAS the Borrower, the Administrative Agent and the Lenders have agreed to amend the Credit Agreement for the purposes and on the terms and conditions set out in this fifth amending agreement and consent (this “ Agreement ”).

NOW THEREFORE in consideration of the mutual obligations contained herein and for other consideration, the receipt and sufficiency of which are acknowledged, the parties agree as follows: ARTICLE 1 INTERPRETATION

1.1 Definitions

Words and expressions defined or given extended meanings in the Credit Agreement are used with the same respective defined or extended meanings in this Agreement. Unless otherwise noted, references to Sections relate to Sections of the Credit Agreement.

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1.2 Reference to Agreements

Each reference in this Agreement to any agreement (including this Agreement and any other defined term that is an agreement) shall be construed so as to include such agreement (including any attached schedules, appendices and exhibits) and each change thereto made at or before the time in question.

1.3 Headings, etc.

The division of this Agreement into Articles, Sections and Subsections and the insertion of headings are for the convenience of reference only and shall not affect the construction or interpretation of this Agreement. The terms “ this fifth amending agreement ”, “ this Agreement ”, “ hereof ”, “ hereunder ” and similar expressions refer to this Agreement and not to any particular Article, Section, Subsection, paragraph, subparagraph, clause or other portion of this Agreement.

1.4 Grammatical Variations

In this Agreement, unless the context otherwise requires, (i) words and expressions (including words and expressions (capitalized or not), which are defined, given extended meanings or incorporated by reference herein) in the singular include the plural and vice versa (the necessary changes being made to fit the context), (ii) words in one gender include all genders and (iii) grammatical variations of words and expressions (capitalized or not) which are defined, given extended meanings or incorporated by reference in this Agreement shall be construed in like manner. ARTICLE 2 AMENDMENTS

2.1 Amendments

Subject to Section 3.1 of this Agreement, the Credit Agreement is hereby amended as follows:

2.1.1 Defined Terms . Section 1.1 of the Credit Agreement is hereby amended by deleting the reference to “EGC,” in the definition of “ Immaterial Subsidiaries ”.

Schedules G and I. Schedules G and I of the Credit Agreement are hereby deleted in their entirety and replaced with Schedules G and I attached hereto.

ARTICLE 3 CONDITIONS PRECEDENT TO AMENDMENTS

3.1 Conditions Precedent to Amendments

3.1.1 The amendments to the Credit Agreement set out in Article 2 of this Agreement (collectively, the “ Amendments ”) shall not become effective unless and until all the following conditions precedent are satisfied or waived by the Lenders (the “ Effective Date ”):

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• (a) each of the signatories hereto has executed and delivered this Agreement;

• (b) each of the Borrower, NXGSA, MCSA and EGC (the “ Relevant Obligors ”) shall have duly executed and delivered to the Administrative Agent the Credit Documents and amendments and/or confirmations to the Credit Documents to which each is a party and required as a result of the Amendments and the NXGSA Reorg (as defined below), in form and substance satisfactory to the Administrative Agent;

• (c) the Administrative Agent and its legal counsel shall be satisfied, acting reasonably, that all necessary approvals, acknowledgements, directions and consents have been given and that all relevant laws have been complied with in respect of all agreements and transactions referred to herein;

• (d) the Administrative Agent has received, in form and substance satisfactory to the Administrative Agent, requisite information to identify EGC under the applicable “know your client” and anti-money laundering/anti-terrorism legislation and regulations, delivered sufficiently in advance for each Lender to complete such identification;

• (e) the Borrower shall cause to be delivered to the Administrative Agent, in form and substance satisfactory to the Administrative Agent:

• (i) a Closing Certificate of each of the Relevant Obligors;

• (ii) a certificate of status or good standing or a certificate to similar effect for each Relevant Obligor, issued by the appropriate governmental body or agency; and

• (iii) an opinion of legal counsel to the Relevant Obligors relating to the enforceability of the Credit Agreement (as amended by this Agreement and the first amending agreement, the second amending agreement, the third amending agreement, the fourth amending agreement and the fifth amending agreement referenced in the first recital hereof) and such other matters as the Administrative Agent may reasonably request; and

• (f) except as otherwise provided in the relevant amendments and/or confirmations to the Security Documents, all documents and instruments shall have been properly registered, recorded and filed in all places which are desirable or required to make effective the Security created or intended to be created by the Obligors in favour of the Administrative Agent pursuant to the Security Documents and to ensure the perfection and the intended priority of such Security.

3.1.2 The Credit Agreement as amended by the Amendments shall constitute one agreement, and the Credit Agreement as so amended is hereby ratified and confirmed by the parties hereto.

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3.1.3 Future References to the Credit Agreement. On and after the date of this Agreement, each reference in the Credit Agreement to “this Agreement”, “hereunder”, “hereof”, or words of like import referring to the Credit Agreement, and each reference in any related document to the “Credit Agreement”, “thereunder”, “thereof”, or words of the like import relating to the Credit Agreement, shall mean and be a reference to the Credit Agreement as amended by the Amendments. The Credit Agreement, as amended hereby, is and shall continue to be in full force and effect and is hereby in all respects ratified and confirmed.

ARTICLE 4 REPRESENTATIONS AND WARRANTIES

4.1 Representations and Warranties of the Borrower

The Borrower represents and warrants to and in favour of each of the Lenders as

follows:

4.1.1 General Warranties. The representations and warranties made by it to the Lenders under Article 10 of the Credit Agreement (except for those which are made as of a specific date) are true, accurate and complete in all respects as if they were made on the date of execution and delivery hereof with references therein to the Credit Agreement being replaced by references to this Agreement and the Credit Agreement as amended by the Amendments, and such representations and warranties are hereby so repeated, it being understood that to the extent such representations and warranties relate solely to a specifically identified earlier date they need only be true and correct as of such earlier date.

4.1.2 Event of Default Warranty. The Borrower represents and warrants that no Default or Event of Default exists or would result from the Amendments becoming effective. ARTICLE 5 GENERAL

5.1 NXGSA Reorganization

Notwithstanding anything to the contrary in the Credit Documents but subject to the following sentence, the Lenders hereby consent to (a) the Capital Reorganization of NXGSA, pursuant to which (i) MCSA will transfer all of its Shares of NXGSA to the Borrower in repayment of a portion of its Indebtedness to the Borrower (the “ MCSA Transfer ”) and (ii) the Borrower will transfer all of its Shares of NXGSA to EGC (collectively, the “ NXGSA Reorg ”) and (b) waiving the requirement for any interim guarantee and security documents to be entered into in connection with the MCSA Transfer. The foregoing consents are conditional upon satisfaction of each of the following conditions:

• (a) On the Effective Date, the Relevant Obligor shall deliver to the Administrative Agent the following, each to be in form and substance satisfactory to the Administrative Agent:

• (i) a duly executed amendment to the share pledge agreement dated April 18, 2019, as amended on June 26, 2019 and on March 31, 2020 among the

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Borrower, MCSA and the Administrative Agent governed by the laws of Brazil, regarding the pledge of the Shares of NXGSA and to be granted by each of the Relevant Obligors in favour of the Administrative Agent;

• (ii) a duly executed general security agreement granted by EGC in favour of the Administrative Agent governed by the laws of British Columbia;

• (iii) share certificates representing all of the issued and outstanding Shares of EGC together with executed stock transfers and powers of attorney; and

• (iv) a duly executed guarantee granted by EGC in favour of the Administrative Agent governed by the laws of British Columbia.

5.2 Further Assurances

The Borrower shall, at their own expense, do, make, execute or deliver all such further acts, documents and things in connection with this Agreement as the Administrative Agent may reasonably require for the purpose of giving effect to this Agreement, all promptly following the request of the Administrative Agent.

5.3 Credit Document

This Agreement shall constitute a Credit Document.

5.4 Fees and Expenses

The Borrower shall, promptly following the request by the Administrative Agent, reimburse the Administrative Agent on a full indemnity basis for all reasonable out-of-pocket expenses incurred by the Administrative Agent in connection with the preparation, settlement, execution and delivery of this Agreement and the entry into effect of the Amendments.

5.5 Benefit & Burden

This Agreement shall enure to the benefit of and be binding upon the parties hereto, their respective successors and each assignee of some or all of the rights or obligations of the parties under the Credit Documents permitted by the Credit Agreement.

5.6 Counterparts

This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original and all of which taken together shall be deemed to constitute one and the same agreement counterpart. Transmission of a copy of an executed signature page of this Agreement by facsimile or e-mail in pdf format by one party hereto to each other party hereto shall be as effective as delivery of an original manually executed counterpart hereof to each other party hereto.

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5.7 Governing Law

This Agreement shall be governed by, and construed and interpreted in accordance with, the laws in force in the Province of British Columbia and the federal laws of Canada applicable therein.

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IN WITNESS WHEREOF the parties hereto have executed this agreement on the date first written above.

Ero Copper Corp. Suite 1050 625 Howe Street Vancouver, British Columbia V6C 2T6

Attention: [Redacted]

ERO COPPER CORP.

By: ("Signed") Name: Title:

Telefax: [Redacted] Email: [Redacted]

By: ("Signed") Name: Title:

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The Bank of Nova Scotia Global Banking and Markets - Loan Syndications 40 King Street West, 62[nd] Floor Toronto, Ontario M5W 2X6

Attention: [Redacted] Telefax: [Redacted] Email: [Redacted]

THE BANK OF NOVA SCOTIA, as Administrative Agent

By: ("Signed") Name: Title:

By: ("Signed") Name: Title:

The Bank of Nova Scotia Corporate Banking - Global Mining 40 King Street West, 62[nd] Floor Toronto, Ontario M5W 2X6

Attention: [Redacted] Telefax: [Redacted] Email: [Redacted]

THE BANK OF NOVA SCOTIA, as Lender

By: ("Signed") Name: Title:

By: ("Signed") Name: Title:

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Bank of Montreal 885 West Georgia Street 17[th] Floor Vancouver, British Columbia V6C 3E8

Attention: [Redacted] Telefax: [Redacted] Email: [Redacted]

BANK OF MONTREAL, as Lender

By: ("Signed") Name: Title: By: Name: Title:

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SCHEDULE G CORPORATE STRUCTURE

==> picture [529 x 354] intentionally omitted <==

----- Start of picture text -----

Ero Copper Corp.
(British Columbia)
100%
Vale do
Curaca
Property ~99.6% Ero Copper (US) Ltd.
100% (Delaware)
100%
Mineração Caraíba S.A. Ero Gold Corp.
(Brazil) (British Columbia)
100%
100% ~96.6%
100%
Boa
Esperanca
Property Mineração Boa Esperança S/A NX Gold S.A.
(Brazil) (Brazil)
100%
Mineração Caraíba International Inc.
(BVI)
NX Gold
Property
----- End of picture text -----

SCHEDULE I SECURITY DOCUMENTS

Canadian law Documents

• (a) General Security Agreement dated December 21, 2017 between the Borrower and the Administrative Agent, governed by the laws of the Province of British Columbia.

• (b) General Security Agreement dated May 29, 2020 between Ero Gold Corp. and the Administrative Agent, governed by the laws of the Province of British Columbia.

• (c) Guarantee dated May 29, 2020 between Ero Gold Corp. and the Administrative Agent, governed by the laws of the Province of British Columbia.

Brazilian law Documents

• (a) Share Pledge Agreement dated December 14, 2018, governed by the laws of Brazil and entered into by Ero Copper Corp., Mineração Caraíba S.A. and the Administrative Agent with respect to the shares issued by Mineração Caraíba S.A. and held by Ero Copper Corp., as amended by the First Amendment to the Share Pledge Agreement dated June 26, 2019 and entered into by Ero Copper Corp., Mineração Caraíba S.A. and the Administrative Agent and by the Second Amendment to the Share Pledge Agreement dated March 31, 2020 and entered into by Ero Copper Corp., Mineração Caraíba S.A. and the Administrative Agent.

• (b) Share Pledge Agreement dated April 18, 2019, governed by the laws of Brazil and entered into by Ero Copper Corp., Mineração Caraíba S.A., NX Gold S.A. and the Administrative Agent with respect to the shares issued by NX Gold S.A. and held by Ero Copper Corp. and by Mineração Caraíba S.A., as amended by the First Amendment to the Share Pledge Agreement dated June 26, 2019 and entered into by Ero Copper Corp., Mineração Caraíba S.A., NX Gold S.A. and the Administrative Agent, by the Second Amendment to the Share Pledge Agreement dated March 31, 2020 and entered into by Ero Copper Corp., Mineração Caraíba S.A., NX Gold S.A. and the Administrative Agent and by the Third Amendment to the Share Pledge Agreement dated May 29, 2020 and entered into by Ero Copper Corp., Mineração Caraíba S.A., NX Gold S.A., Ero Gold Corp. and the Administrative Agent.

• (c) Share Pledge Agreement dated March 31, 2020, governed by the laws of Brazil and entered into by Mineração Caraíba S.A., NX Gold S.A. and the Administrative Agent with respect to the shares issued by Mineração Caraíba S.A. and held by NX Gold S.A.

• (d) Receivables Pledge Agreement dated December 14, 2018, governed by the laws of Brazil and entered into by Ero Copper Corp., Mineração Caraíba S.A. and the Administrative Agent with respect to certain receivables held by Ero Copper

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Corp., as amended by the First Amendment to the Receivables Pledge Agreement dated June 26, 2019 and entered into by Ero Copper Corp., Mineração Caraíba S.A. and the Administrative Agent and by the Second Amendment to the Receivables Pledge Agreement dated March 31, 2020 and entered into by Ero Copper Corp., Mineração Caraíba S.A. and the Administrative Agent.

• (e) Letter of Guarantee dated December 14, 2018, governed by the laws of Brazil and granted by Mineração Caraíba S.A. in favor of the Finance Parties, as represented by the Administrative Agent, entered into by Mineração Caraíba S.A. and the Administrative Agent, as amended by the First Amendment to the Letter of Guarantee dated June 26, 2019 and entered into by Mineração Caraíba S.A. and the Administrative Agent and by the Second Amendment to the Letter of Guarantee dated March 31, 2020 and entered into by Mineração Caraíba S.A. and the Administrative Agent.

• (f) Letter of Guarantee dated April 18, 2019, governed by the laws of Brazil and granted by NX Gold S.A. in favor of the Finance Parties, as represented by the Administrative Agent, entered into by NX Gold S.A. and the Administrative Agent, as amended by the First Amendment to the Letter of Guarantee dated June 26, 2019 and entered into by NX Gold S.A. and the Administrative Agent and by the Second Amendment to the Letter of Guarantee dated March 31, 2020 and entered into by NX Gold S.A. and the Administrative Agent.

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