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GREAT BOULDER RESOURCES LIMITED Capital/Financing Update 2025

Aug 17, 2025

64967_rns_2025-08-17_babcb396-d89c-4603-88f9-90b1483a6020.pdf

Capital/Financing Update

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ASX Announcement
18 AUGUST 2025
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HIGH-GRADE INTERSECTIONS BOLSTER EAGLEHAWK

PLUS FURTHER HIGH GRADES IN METALLURGICAL DRILLING AT IRONBARK

HIGHLIGHTS

  • Resource definition drilling at Eaglehawk has intersected new high-grade gold mineralisation outside the current lode interpretation, highlights include:

Hole 5EHRC003 – Intersected four high-grade zones

  • 8m @ 29.18g/t Au from 128m, incl. 4m @ 54.80g/t Au from 128m;

  • 12m @ 4.63g/t Au from 68m;

  • 28m @ 1.73g/t Au, incl. 5m @ 3.74g/t Au from 182m; and

  • 4m @ 14.85g/t Au from 196m to End of Hole

Hole 25EHRC006 - 6m @ 5.11g/t Au from 123m, incl. 2m @ 12.58g/t Au from 124m

Hole 25EHRC008 - 6m @ 7.03g/t Au from 98m, incl. 1m @ 26.20g/t Au from 99m

  • Ironbark infill drilling delivered grades exceeding the current resource grade with hole 25IBWR004 intersecting high-grade gold at the bottom of the current resource model Hole 25IBWR004 - 9m @ 4.97g/t Au from 144m, incl. 1m @ 33.40g/t Au from 149m and Hole 25IBWR002 - 11m @ 3.72g/t Au from 105m, incl. 7m @ 5.33g/t Au from 105m

  • Assays from a further 17 RC holes at Eaglehawk are expected shortly

  • RC drilling is ongoing at Side Well South completing resource definition drilling

Great Boulder Resources (“ Great Boulder ” or the “ Company ”) (ASX: GBR ) is pleased to provide an update on exploration results at the Company’s flagship Side Well Gold Project (“ Side Well ”) near Meekatharra in Western Australia which hosts a Mineral Resource Estimate (“ MRE ”) of 668,000oz @ 2.8 g/t Au.

Great Boulder’s Managing Director, Andrew Paterson commented:

“These are some fantastic intersections from Eaglehawk, which demonstrates the capacity of this gold system to deliver high-grade surprises! We need to do more drilling to confirm the orientation of these new zones, but our geological logging suggests there may be two or three new west-dipping high-grade veins and possibly one thicker subvertical zone. All of these intersections are outside the dacite target lithology which is where we’ve seen the really high grades in previous drilling.”

E: [email protected] GREATBOULDER.COM.AU ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

ASX Announcement 18 AUGUST 2025

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“Our waste characterisation drilling at Ironbark has also delivered good news, with an intersection at the bottom of the current resource which is thicker and higher grade than we expected. That result provides further scope for depth extensions under the current Ironbark pit design.”

“The RC rig is now completing a phase of resource definition drilling at Side Well South and we’re expecting a second rig on site at the end of August, so the team will be very busy for the rest of the year with a combination of resource growth drilling and testing new discovery targets.”

27 RC holes were drilled for 4,544m at Eaglehawk. This included 21 RC resource definition holes within the Eaglehawk deposit, and six RC holes in the “gap” area between Mulga Bill and Eaglehawk (Figure 1). Assays have been received for the first 10 holes, with the balance expected to be received shortly.

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FIGURE 1: RECENT HIGH-GRADE RESULTS FROM EAGLEHAWK

E: [email protected] GREATBOULDER.COM.AU ABN 70 611 695 955

ASX Code: GBR P: +61 8 9321 6037

Contact: Andrew Paterson, Managing Director Level 1, 51 Colin St West Perth WA 6005

ASX Announcement

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18 AUGUST 2025

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Highlights from the results received to date include:

  • 12m @ 4.63g/t Au from 68m, including 5m @ 8.62g/t Au from 72m in 25EHRC003

  • 8m @ 29.18g/t Au from 128m, including 4m @ 54.80g/t Au from 128m in 25EHRC003

  • 28m @ 1.73g/t Au, including 5m @ 3.74g/t Au from 182m in 25EHRC003

  • 4m @ 14.85g/t Au from 196m to EOH (4m composite sample) in 25EHRC003

  • 6m @ 5.11g/t Au from 123m, including 2m @ 12.58g/t Au from 124m in 25EHRC006

  • 6m @ 7.03g/t Au , including 1m @ 26.20g/t Au from 99m in 25EHRC008

Further drilling is required to confirm the orientations of the multiple mineralised zones intersected by hole 25EHRC003 (Figure 2). High-grade mineralisation remains open beyond the bottom of the hole, with a 4m end-of-hole (EOH) composite sample grading 14.85g/t Au .

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FIGURE 2: CROSS-SECTION SHOWING THE MULTIPLE HIGH-GRADE INTERSECTIONS IN HOLE 25EHRC003

E: [email protected] GREATBOULDER.COM.AU ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

ASX Announcement 18 AUGUST 2025

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25EHRC003 is interpreted to have intersected two or possibly three west-dipping high-grade structures, including the intersection of 12m @ 4.63g/t Au from 68m which is partly influenced by supergene effects due to weathering. The broader, lower intersection of 28m @ 1.73g/t Au has characteristics of the sub-vertical, shear-hosted lodes similar to those referred to as the Malvern Lodes within Mulga Bill. These lodes have excellent continuity along strike (at Mulga Bill) but have not yet been confirmed within the Eaglehawk deposit.

The thickness and orientation of the end-of-hole mineralisation is unknown at this point, pending further drilling.

Five RC holes for 655m were drilled at Ironbark as part of the ongoing technical studies required for a mining approval application. These holes were designed to provide material for waste rock characterisation, with some also positioned to provide additional material for metallurgical samples within the deposit. High-grade intersections from this program include:

  • 9m @ 4.97g/t Au from 144m, including 1m @ 33.40g/t Au from 149m in 25IBWR004

  • 11m @ 3.72g/t Au from 105m, including 7m @ 5.33g/t Au from 105m in 25IBWR002.

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FIGURE 3: IRONBARK CROSS-SECTION SHOWING HOLE 25IBWR004 IN RELATION TO THE MINERAL RESOURCE AND THE SCOPING STUDY PIT DESIGN

E: [email protected] GREATBOULDER.COM.AU ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

ASX Announcement

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18 AUGUST 2025

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The high-grade intersection in hole 25IBWR004 is within the middle of the deposit and at the bottom of the current mineral resource (Figure 3), with higher gold grades than previously interpreted from earlier drilling. This provides additional scope for depth extensions below the current resource.

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FIGURE 4: PLAN VIEW OF RECENT RESULTS FROM IRONBARK

E: [email protected] GREATBOULDER.COM.AU ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

ASX Announcement

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Next Steps

The RC rig has now returned to Side Well South to complete a phase of RC holes designed to continue defining recently discovered gold mineralisation north of the historic Golden Bracelet area. This drilling is intended to define mineralisation with sufficient confidence to allow the estimation of an initial Mineral Resource Estimate.

An AC rig is expected to arrive at Side Well towards the end of August. This rig will allow the Side Well growth and discovery program to be accelerated throughout the remainder of the year and into 2026. Further information on planned drilling will be provided in future market updates.

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FIGURE 5: A PROJECTED LONG SECTION THROUGH MULGA BILL & EAGLEHAWK

This announcement has been approved by the Great Boulder Board.

For further information contact:

Andrew Paterson Managing Director Great Boulder Resources Limited [email protected] www.greatboulder.com.au

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Media Lucas Robinson Corporate Storytime +61 408 228 889 [email protected]

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Follow GBR on LinkedIn

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Follow GBR on Twitter

E: [email protected] GREATBOULDER.COM.AU ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

ASX Announcement 18 AUGUST 2025

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COMPETENT PERSON’S STATEMENT

The information in this Announcement that relates to Exploration Targets and Exploration Results is based upon work undertaken by Mr Andrew Paterson who is a Member of the Australasian Institute of Geoscientists (AIG). Mr Paterson has sufficient experience that is relevant to the style of mineralisation and type of deposit under consideration and to the activity which he is undertaking to qualify as a ‘Competent Person’ as defined in the 2012 Edition of the ‘Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves’ (JORC Code). Mr Paterson is an employee of Great Boulder Resources and consents to the inclusion in the report of the matters based on their information in the form and context in which it appears.

The information that relates to Mineral Resources was previously reported by the Company in its announcement to the ASX on 16 November 2023 ‘Side Well Mineral Resource Increases to 688Koz Au’, a copy of which is available on the Company’s website at https://www.greatboulder.com.au/investors/asx-announcements/. The Company is not aware of any new information or data that materially affects the information included in this announcement and that all material assumptions and technical parameters underpinning the estimates continue to apply and have not material changed. The Company confirms that the form and context in which the Competent Person’s findings are presented have not been materially modified from the original market announcement.

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FIGURE 6: THE SIDE WELL GOLD PROJECT IS STRATEGICALLY LOCATED, SURROUNDED BY MINING AND CIVIL INFRASTRUCTURE

E: [email protected] GREATBOULDER.COM.AU ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

ASX Announcement

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18 AUGUST 2025

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FIGURE 7: SIDE WELL GOLD PROJECT DEPOSITS AND OTHER PROSPECTS

TABLE 1: SIDE WELL MINERAL RESOURCE SUMMARY, NOVEMBER 2023

Indicated Indicated Indicated Inferred Inferred Inferred Total
Deposit Type Cut-off Tonnes
(kt)
Au
(g/t)
Ounces Tonnes
(kt)
Au
(g/t)
Ounces Tonnes
(kt)
Au
(g/t)
Ounces
Mulga Bill Open Pit
U/ground
0.5
1.0
1,667
733
3.1
3.5
169,000
83,000
2,982
1,130
1.9
3.6
183,000
132,000
4,649
1,863
2.4
3.6
352,000
216,000
Subtotal 2,399 3.3 252,000 4,112 2.4 316,000 6,511 2.7 568,000
Ironbark Open Pit
U/ground
0.5
1.0
753
0
3.7
0.0
88,000
0
186
0
1.9
0.0
11,000
0
938
0
3.3
0.0
100,000
0
Subtotal 753 3.7 88,000 186 1.9 11,000 938 3.3 100,000
Total 3,152 3.4 340,000 4,298 2.4 327,000 7,450 2.8 668,000

Subtotals are rounded for reporting purposes. Rounding errors may occur.

E: [email protected] ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

GREATBOULDER.COM.AU

ASX Announcement

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18 AUGUST 2025

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TABLE 2: SIGNIFICANT INTERSECTIONS: EAGLEHAWK RC DRILLING

Prospect Hole ID From To Width Grade
Comments
Eaglehawk 25EHRC001 96 98 2 1.12
100 102 2 1.01
25EHRC002 76 77 1 0.74
80 81 1 0.90
84 88 4 0.33 4m composite
139 140 1 0.75
25EHRC003 24 32 8 0.17 4m composites
68 80 12 4.634m comps 68 - 76m
Including 72 77 5 8.624m comp 72 - 76m
128 136 8 29.184m composites
Including 128 132 4 54.80
160 188 28 1.734m comps to 180m
182 187 5 3.74
196 200 4 14.854m composite
25EHRC004 76 84 8 0.67 4m composites
89 91 2 2.25
25EHRC005 80 84 4 0.12 4m composite
88 92 4 0.14 4m composite
116 120 4 0.18 4m composite
120 121 1 1.57
131 132 1 1.54
135 138 3 1.20
25EHRC006 28 32 4 0.48 4m composite
40 44 4 0.41 4m composite
115 116 1 0.53
119 121 2 0.77
123 129 6 5.11
Including 124 126 2 12.58
168 172 4 0.19 4m composite
188 192 4 0.10 4m composite
200 204 4 0.13 4m composite
25EHRC007 49 50 1 0.61
64 68 4 0.36 4m composite
84 87 3 0.87
116 120 4 0.15 4m composite
25EHRC008 32 36 4 0.27 4m composite
67 68 1 0.50
69 70 1 0.62
98 104 6 7.03
Including 99 100 1 26.20
107 108 1 0.83
118 123 5 0.97
130 131 1 0.79

ASX Code: GBR Contact: Andrew Paterson, Managing Director E: [email protected] GREATBOULDER.COM.AU P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005 ABN 70 611 695 955

ASX Announcement

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18 AUGUST 2025

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25EHRC009
77
78
1
0.79
83
84
1
0.60
25EHRC009
77
78
1
0.79
83
84
1
0.60
25EHRC009
77
78
1
0.79
83
84
1
0.60
25EHRC010
84
88
4
0.11 4m composite
96
100
4
2.41 4m composite
164
165
1
2.28

Significant intersections are reported at a 0.1g/t Au cut-off for 4m composite samples and a 0.5g/t Au cut-off for 1m samples.

TABLE 3: SIGNIFICANT INTERSECTIONS: IRONBARK WASTE CHARACTERISATION DRILLING

Prospect Hole ID From To Width Grade
Comments
Ironbark 25IBWR001 28 32 6 1.02 4m composite
38 39 1 1.77
47 48 1 0.60
53 64 11 0.68 4m composites
25IBWR002 4 8 4 0.23 4m composite
94 96 2 2.48
105 116 11 3.724m composites
including 105 112 7 5.334m composite
25IBWR003 16 40 24 0.37 4m composites
25IBWR004 144 153 9 4.974m composite
including 149 150 1 33.40
156 157 1 0.65
160 164 4 0.22 4m composite
25IBWR005 36 40 4 0.53 4m composite
46 47 1 0.79

Significant intersections are reported at a 0.1g/t Au cut-off for 4m composite samples and a 0.5g/t Au cut-off for 1m samples.

TABLE 4: SIGNIFICANT INTERSECTIONS: MULGA BILL AIR-CORE DRILLING

Prospect Hole ID From To Width Grade
Comments
Mulga Bill 25SWAC196 32 36 4 0.12 4m Composite
104 111 4 0.27 EOH 4m Composites
25SWAC197 92 96 4 0.58 4m Composite
25SWAC198 40 44 4 0.10 4m Composite
109 113 4 1.57EOH
Including 109 110 1 2.82
25SWAC199 24 28 4 0.10 4m Composite
84 88 4 0.23 4m Composite
104 111 7 0.37 4m Composite
25SWAC200 107 108 1 0.56
124 127 4 0.11 EOH. 4m composite
25SWAC201 0 97 97 No significant intersection

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

E: [email protected] GREATBOULDER.COM.AU ABN 70 611 695 955

ASX Announcement

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25SWAC202
64
68
4
0.89 4m Composite
25SWAC202
64
68
4
0.89 4m Composite
25SWAC202
64
68
4
0.89 4m Composite
25SWAC203
0
112
112 No significant intersection
25SWAC204
36
40
4
0.13 4m composite
76
80
4
0.18 4m composite
84
90
6
0.25 4m composite
25SWAC205
20
24
4
0.12 4m composite
28
40
12
0.32 4m composites
44
48
4
0.20 4m composite
104
111
7
1.23 EOH. 4m and 3m composite
25SWAC206
60
64
4
0.14 4m composite
72
84
12
1.454m composites
25SWAC207
48
52
4
0.11 4m composite
64
80
16
0.27 4m composites
25SWAC208
64
68
4
0.66 4m composite
25SWAC209
60
64
4
0.12 4m composite
68
72
4
0.30 4m composite
76
88
12
0.24 4m composites
25SWAC210
57
58
1
0.99
68
70
2
0.16 EOH. 2m Composite
25SWAC211
68
72
4
0.29 4m composite

Significant intersections are reported at a 0.1g/t Au cut-off for 4m composite samples and a 0.5g/t Au cut-off for 1m samples.

TABLE 5: COLLAR DETAILS: RC DRILLING (GDA94, ZONE 50)

Hole ID Prospect Easting Northing RL Dip Azi Total
(Mag) Depth
25IBWR001 Ironbark 660106 7059126 518 -60 90 92
25IBWR002 Ironbark 660060 7059025 517 -60 90 165
25IBWR003 Ironbark 660114 7058950 517 -60 90 86
25IBWR004 Ironbark 660003 7058875 517 -60 90 212
25IBWR005 Ironbark 660061 7058774 517 -60 90 100
25EHRC001 Eaglehawk 658411 7061625 509 -60 90 120
25EHRC002 Eaglehawk 658438 7061676 509 -60 90 160
25EHRC003 Eaglehawk 658331 7061726 509 -60 90 200
25EHRC004 Eaglehawk 658430 7061725 509 -60 90 120
25EHRC005 Eaglehawk 658412 7061800 509 -60 90 176
25EHRC006 Eaglehawk 658368 7061800 509 -60 90 207
25EHRC007 Eaglehawk 658490 7061900 509 -60 90 195
25EHRC008 Eaglehawk 658465 7061952 509 -60 90 165
25EHRC009 Eaglehawk 658384 7061950 509 -60 90 159
25EHRC010 Eaglehawk 658458 7062025 509 -60 90 207
25EHRC011 Eaglehawk 658490 7062050 509 -60 90 171

ASX Code: GBR Contact: Andrew Paterson, Managing Director E: [email protected] GREATBOULDER.COM.AU P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005 ABN 70 611 695 955

ASX Announcement

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25EHRC012 Eaglehawk 658413 7062050 509 -60 90 194
25EHRC013 Eaglehawk 658368 7062050 509 -60 90 230
25EHRC014 Eaglehawk 658517 7062100 509 -60 90 182
25EHRC015 Eaglehawk 658434 7062225 508 -60 90 186
25EHRC016 Eaglehawk 658514 7062300 509 -60 90 152
25EHRC017 Eaglehawk 658478 7062400 508 -60 90 158
25EHRC018 Eaglehawk 658463 7062350 509 -60 90 199
25EHRC019 Eaglehawk 658594 7062650 509 -60 90 156
25EHRC020 Eaglehawk 658533 7062650 509 -60 90 172
25EHRC021 Eaglehawk 658582 7062700 507 -60 90 165
25MBRC021 Mulga Bill 658414 7061500 510 -60 87 159
25MBRC022 Mulga Bill 658474 7061475 510 -60 87 111
25MBRC023 Mulga Bill 658414 7061475 510 -60 87 171
25MBRC024 Mulga Bill 658504 7061450 510 -60 87 102
25MBRC025 Mulga Bill 658438 7061425 510 -60 87 144
25MBRC026 Mulga Bill 658378 7061450 510 -60 87 183

TABLE 6: COLLAR DETAILS: AC DRILLING (GDA94, ZONE 50)

Hole ID Prospect Easting Northing RL Dip Azi Total
(Mag) Depth
25SWAC196 Mulga Bill 658724 7060850 511 -60 90 111
25SWAC197 Mulga Bill 658664 7060850 511 -60 90 123
25SWAC198 Mulga Bill 658604 7060850 511 -60 90 113
25SWAC199 Mulga Bill 658544 7060850 511 -60 90 117
25SWAC200 Mulga Bill 658484 7060850 511 -60 90 127
25SWAC201 Mulga Bill 658783 7060975 511 -60 90 97
25SWAC202 Mulga Bill 658735 7060975 511 -60 91 102
25SWAC203 Mulga Bill 658685 7060975 511 -60 87 112
25SWAC204 Mulga Bill 658634 7060975 511 -60 90 108
25SWAC205 Mulga Bill 658653 7060975 511 -60 90 111
25SWAC206 Mulga Bill 658674 7061150 511 -60 90 94
25SWAC207 Mulga Bill 658614 7061150 511 -60 90 100
25SWAC208 Mulga Bill 658554 7061150 511 -60 90 93
25SWAC209 Mulga Bill 658675 7061253 511 -60 90 90
25SWAC210 Mulga Bill 658614 7061258 511 -60 90 70
25SWAC211 Mulga Bill 658557 7061257 511 -60 90 90

E: [email protected] ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

GREATBOULDER.COM.AU

ASX Announcement

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ABOUT GREAT BOULDER RESOURCES

Great Boulder is a mineral exploration company with a portfolio of highly prospective gold and base metals assets in Western Australia ranging from greenfields through to advanced exploration. The Company’s core focus is the Side Well Gold Project at Meekatharra in the Murchison gold field, where exploration has defined a Mineral Resource of 7.45Mt @ 2.8g/t Au for 668,000oz Au (340koz @ 3.4g/t Au Indicated, 327koz @ 2.4g/t Au Inferred). The Company is also progressing earlystage exploration at its Wellington Base Metal Project located in an emerging MVT province. With a portfolio of highly prospective assets plus the backing of a strong technical team, the Company is well positioned for future success.

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CAPITAL STRUCTURE

935.4M ~$12.5M

SHARES ON ISSUE ASX:GBR

CASH As at 30 June 25

~$51M

Nil

MARKET CAP DEBT At $0.062/sh As at 31 March 25

$900k $263k LISTED INVESTMENT DAILY LIQUIDITY Cosmo Metals (ASX:CMO) Average 30-day value traded 80.0M ~36% UNLISTED OPTIONS TOP 20 OWNERSHIP

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Exploring WA Gold & Developing a Technically focused Undertaking smart, Base Metal assets, significant high-grade, exploration team with innovative & located in proximity to large scale gold a strong track record systematic exploration operating mines & system at Side Well of discovery infrastructure

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Ongoing drilling at multiple projects providing consistent, material newsflow

E: [email protected] GREATBOULDER.COM.AU ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

ASX Announcement

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Appendix 1 - JORC Code, 2012 Edition Table 1 (GBR Drilling, Side Well Project)

Section 1 Sampling Techniques and Data

(Criteria in this section apply to all succeeding sections.)

Criteria Commentary
Sampling techniques At the Side Well Project GBR has collected data from auger sampling and from AC, RC and Diamond
drilling techniques. This section encompasses all four methods.
RC samples are collected into calico bags over 1m intervals using a cyclone splitter. The residual bulk
samples are placed in lines of piles on the ground. 2 cone splits are taken off the rig splitter for RC
drilling. Visually prospective zones are sampled over 1m intervals and sent for analysis while the rest
of the hole is composited over 4m intervals by taking a scoop sample from each 1m bag.
Core samples are selected visually based on observations of alteration and mineralisation and
sampled to contacts or metre intervals as appropriate. Once samples are marked the core is cut in
half longitudinally with one half taken for assay and the other half returned to the core tray.
All core is oriented in order to measure and record structural orientations.
AC samples are placed in piles on the ground with 4m composite samples taken using a scoop.
Any composite samples assaying 0.1g/t Au or more are re-assayed in 1m intervals.
Auger samples are recovered from the auger at blade refusal depth. Auger drilling is an open-hole
technique.
Drilling techniques Industry standard drilling methods and equipment were utilised.
Auger drilling was completed using a petrol-powered hand-held auger.
Drill sample recovery Sample recovery data is noted in geological comments as part of the logging process. Sample
condition has been logged for every geological interval as part of the logging process. Where water
is encountered during drilling the resultant sample quality is noted as being dry, moist or wet.
No quantitative twinned drilling analysis has been undertaken.
Logging Geological logging of drilling followed established company procedures. Qualitative logging of
samples includes lithology, mineralogy, alteration, veining and weathering. Abundant geological
comments supplement logged intervals.
Sub-sampling techniques
and sample preparation
1m cyclone splits and 4m speared composite samples are taken in the field. Samples are prepared
and analysed at ALS Laboratories Perth for RC and diamond drilling and Intertek Laboratories for
the AC drilling and auger soil samples.
Samples are pulverized so that each sample has a nominal grainsize of 85% passing 75 microns. Au
analysis is undertaken using Au-AA26 involving a 50g lead collection fire assay and Atomic
Adsorption Spectrometry (AAS) finish. For AC drilling, Au analysis is undertaken at Intertek using a
50g lead collection fire assay with ICP-OES finish (FA50/OE).
Multi-element analysis is completed at both ALS and Intertek Laboratories. Digestion is completed
using both 4 Acid and Aqua-regia and analysed by ICP-AES and ICP-MS (Intertek code 4A/MS48, ALS
codes ME-MS61, ME-ICP41-ABC).
Quality of assay data
and laboratory tests
All samples are assayed by industry standard techniques: Fire assay for gold; four-acid digest and
aqua regia for multi-element analysis.
Verification of sampling
and assaying
The standard GBR protocol is followed for insertion of standards and blanks with a blank and
standard inserted per 25 for RC drilling and 40 samples for AC drilling. Field Duplicates as second
cone splits are inserted within known ore zones to assess repeatability. Analysis of ME is typically
done on master pulps after standard gold analysis with a company multi-element standard inserted
every 50 samples. No QAQC problems were identified in the results. No twinned drilling has been
undertaken.
Location of data points Sample locations and mapping observations are located and recorded electronically using a handheld
GPS. Coordinates are recorded in GDA94 grid in Zone 50, which is the GDA94 zone for the
Meekatharra area.

ASX Code: GBR Contact: Andrew Paterson, Managing Director E: [email protected] P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005 ABN 70 611 695 955

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Drill holes are positioned using the same technique. Hole collars are initially picked up after drilling
using a handheld GPS. RC and Diamond hole collars are subsequently surveyed with a DGPS for
greater accuracy.
This accuracy is sufficient for the intended purpose of the data.
Data spacing and
distribution
The spacing and location of the majority of drilling in the projects is, by the nature of early
exploration, variable. As each prospect advances the drill spacing is decreased until the confidence
of continuity is sufficient to allow the estimation of a mineral resource. Resource classification (e.g.
Inferred or Indicated) is assigned by an independent resource consultant.
The spacing and location of data is currently only being considered for exploration purposes.
Orientation of data in
relation to geological
structure
Drilling is dominantly perpendicular to regional geological trends where interpreted and practical.
Wherever possible, cross sections are shown to give a visual indication of the relationship between
intersection width and lode thickness.
The spacing and location of the data is currently only being considered for exploration purposes.
Sample security GBR personnel are responsible for delivery of samples from the drill site to the Toll Ipec dispatch
centre in Meekatharra. Samples are transported by Toll Ipec from Meekatharra to the laboratories
in Perth.
Audits or reviews Data review and interpretation by independent consultants on a regular basis. Group technical
meetings are usually held monthly with input from independent expert consultants in the fields of
geochemistry, petrology, structural geology and geophysics.

Section 2 Reporting of Exploration Results

(Criteria listed in the preceding section also apply to this section.)

Criteria Commentary
Mineral tenement and
land tenure status
Side Well tenement E51/1905 is a 48-block exploration license covering an area of 131.8km2
immediately east and northeast of Meekatharra in the Murchison province. The tenement is 75%
owned by Great Boulder, with Zebina Minerals Pty Ltd holding a 25% free-carried interest up to a
decision to mine.
E51/1679 and the adjoining prospecting licences south of E5/1905 are mainly held in agreements
with Mark Selga and Wanbanna Pty Ltd which give GBR an 80% interest in those tenements.
P51/3361, P51/3362, P51/3358, P51,3419 and P51/3425 are 100%-owned by GBR.
A full list of the Company’s tenement interests is included in each quarterly activities report available
on the ASX.
Exploration done by
other parties
The Side Well project has a protracted exploration history but it is relatively unexplored compared
to other regions surrounding Meekatharra.
Geology The Side Well tenement group covers a portion of the Meekatharra-Wydgee Greenstone Belt north
of Meekatharra, WA. The north-northeasterly-trending Archaean Meekatharra-Wydgee Greenstone
Belt, comprises a succession of metamorphosed mafic to ultramafic and felsic and sedimentary rocks
belonging to the Luke Creek and Mount Farmer Groups.
Over the northern extensions of the belt, sediments belonging to the Proterozoic Yerrida Basin
unconformably overlie Archaean granite-greenstone terrain. Structurally, the belt takes the form of
a syncline known as the Polelle syncline. Younger Archaean granitoids have intrusive contacts with
the greenstone succession and have intersected several zones particularly in the Side Well area.
Within the Side Well tenement group, a largely concealed portion of the north-north-easterly
trending Greenstone Belt is defined, on the basis of drilling and airborne magnetic data, to underlie
the area. The greenstone succession is interpreted to be tightly folded into a south plunging syncline
and is cut by easterly trending Proterozoic dolerite dykes.
There is little to no rock exposure at the Side Well prospect. This area is covered by alluvium and
lacustrine clays, commonly up to 60 metres thick. Subcrop exposures of laterite, mafic and ultramafic
rocks are present along the eastern side of the project, however exposure of outcrop is still relatively
poor.

E: [email protected] ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

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Drill hole Information A list of the drill hole coordinates, orientations and intersections reported in this announcement are
provided as an appended table in the relevant announcements for each drilling program.
Data aggregation
methods
Results are reported using cut-off levels relevant to the sample type. For composited samples
significant intercepts are reported for grades greater than 0.1g/t Au with a maximum internal dilution
of 4m. For single metre splits, significant intercepts are reported for grades greater than 0.5g/t Au
with a maximum internal dilution of 3m.
A weighted average calculation may be used to allow for bottom of hole composites that are less
than the standard 4m and when intervals contain composited samples plus 1m split samples. In such
instances the presence of composite samples within the intersection is noted in the comments.
No metal equivalents are used.
Relationship between
mineralisation widths
and intercept lengths
The majority of drilling is conducted using appropriate perpendicular orientations for interpreted
mineralisation. Stratigraphy appears to be steeply dipping to the west however mineralisation may
have a different orientation. Cross sections are shown wherever possible to illustrate relationships
between drilling and interpreted mineralisation.
Diagrams Refer to figures in announcement.
Balanced reporting It is not practical to report all historical exploration results from the Side Well project. Selected
historical intercepts have previously been re-reported by GBR to highlight the prospectivity of the
region, however the vast majority of work on the project has been completed by GBR and reported
in ASX announcements since 14 July 2020.
Other substantive
exploration data
Subsequent to Doray Minerals Limited exiting the project in 2015, private companies have held the
ground with no significant work being undertaken. Wanbanna Pty Ltd has done limited work
consisting mainly of AC drilling around the Burke’s Reward and Golden Bracelet prospect’s further
south.
Further work Further work is discussed in the document.

E: [email protected] ABN 70 611 695 955

ASX Code: GBR Contact: Andrew Paterson, Managing Director P: +61 8 9321 6037 Level 1, 51 Colin St West Perth WA 6005

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