Earnings release
Page 1
REGISTERED OFFICE Sunstone Metals Limited L31, 120 Collins St +61 3 7044 2627 ABN 68 123 184 412 Melbourne VIC 3000 info@sunstonemetals.com.au ASX: STM Australia sunstonemetals.com.au QUARTERLY REPORT Q1 Sept Quarter 2025 Multiple corporate discussions make strong progress Sunstone also targeting an updated Resource ahead of a planned scoping study for the Bramaderos project Highlights Partnership discussions • Due diligence and discussions continue to be undertaken with several parties, with further site visits conducted during the quarter • Discussions have advanced over the quarter and encompass a range of strategic options, including corporate transactions and strategic investments. Notably, corporate -level discussions are at a stage where a formal offer may be finalised Bramaderos Gold and Copper Project, Southern Ecuador • Sunstone is preparing an updated Bramaderos Mineral Resource estimate, primarily to increase the Indicated Resource classification and to support a planned scoping study for Brama-Alba • During the September quarter, Sunstone undertook an extensive surface rock channel sampling program at Brama-Alba, targeting gold soil anomalies to expand the existing known mineralised area and to link Alba to the adjacent Melonal gold-copper porphyry system • Additional assays were reported from the Brama-Alba and Copete porphyry systems, which highlight the scope for ongoing resource growth and expand the footprint of the large cluster of porphyry systems at Bramaderos • Bramaderos has an MRE of 2.7Moz AuEq 1,2 at the Brama -Alba gold-copper porphyry deposit , which is complemented by a porphyry Exploration Target of between 3.3Moz and 8.6Moz AuEq4 within 255Mt to 360Mt at a grade between 0.40 and 0.74g/t AuEq1,2 • An Exploration Target at the nearby Limon gold-silver epithermal deposit of between 0.9Moz and 1.7Moz AuEq within 30Mt to 44Mt at a grade between 0.9 and 1.2g/t AuEq 3,4 highlights the potential for Limon to be established as an open- pit development to complement and unlock the broader Bramaderos porphyry gold-copper-silver discoveries • The potential quantity and grade of the Exploration Target s are conceptual in nature. There has been insufficient exploration to estimate a Resource for the exploration target area reported. It is uncertain if further exploration will result in the estimation of a Resource El Palmar Gold and Copper Project, Northern Ecuador • Maiden Mineral Resource estimate (MRE) of 1.2Moz AuEq8,9 based solely on the outcropping T1 gold- copper porphyry target , which is one of several gold -copper porphyry deposits at El Palmar . T1 has potential to be a large open pit opportunity before undertaking exploration and development of the deeper porphyry opportunities • A high conviction Exploration Target of between 15M and 45Moz AuEq 8,9 has been identified at El Palmar consisting of 1 . 0 B t t o 1 . 2 B t a t a g r a d e b e t w e e n 0 . 3 g / t t o 0 . 7 g / t g o l d a n d 0 . 1 % t o 0 . 3 % c o p p e r f o r contained metal of between 10Moz and 27Moz gold and 1.0 to 3.7Mt copper For personal use only
Page 2
Page 2 of 20 Quarterly Activities Report Period ended 30 September 2025 Corporate highlights • Cash at 30 September 2025 was $2.2 million • $1.6 million of options were exercised by shareholders during the quarter These options were issued to subscribers in the September 2024 Placement and the October 2024 Share Purchase Plan. After 30 September 2025, a further 39 million options have been converted to shares at a strike price of $0.0075 (amounting to $0.3 million in proceeds). There remain a further 259 million in-the-money options outstanding, with a value of $1.9 million, still to be exercised. For any shareholders who would like to enquire about the process to convert options to shares, please email info@sunstonemetals.com.au. Partnership Discussions Sunstone continues to advance partnership opportunities to unlock the value of its substantial gold and copper discoveries. This process has involved several parties accessing Sunstone’s data room and undertaking site visits. Several opportunities and structures have been explored, with some more advanced than others, including: • Corporate level transactions; • Project-level joint venture earn-in agreements; and • Combinations with complementary nearer-term development assets. As a result of these discussions, an attractive opportunity has advanced to a stage where a formal offer may be finalised. Additional parties continue to participate in this process, with the most recent site visits in June and July. Due diligence under signed confidential agreements continues to be undertaken. At this stage, timeframes are unknown, and there is no certainty or assurance that any proposals will be received or, if received, will be acceptable, either in principle or otherwise, or will result in a binding transaction. The Company believes that con fidentiality has not been lost in relation to the discussions mentioned above, and the Company will provide further information when appropriate under its continuous disclosure obligations. For personal use only
Page 3
Page 3 of 20 Quarterly Activities Report Period ended 30 September 2025 Exploration and Development Activities 1. Bramaderos Gold-Copper Project (Sunstone 87.5%) The Bramaderos Project is ideally located immediately adjacent to the Pan American highway in southern Ecuador, and within a reasonable distance of available grid power, supporting the economics of potential future development opportunities. The project has gentle topography with an average elevation of around 1,100m above sea level. It is also supported by nearby commercial airports and significant population centres such as the city of Loja, and has strong community support. Brama-Alba deposit The Brama-Alba deposit, within the Bramaderos concession, contains an initial Mineral Resource estimate of 156Mt at 0.53g/t AuEq for 2.7Moz AuEq1,2 JORC Classification Tonnage (Mt) Au (g/t) Cu (%) Ag (g/t) AuEq (g/t) AuEq4 (Mozs) Indicated 9 0.38 0.09 1.1 0.53 0.2 Inferred 147 0.35 0.11 1.3 0.53 2.5 Total 156 0.35 0.11 1.3 0.53 2.7 In addition, the Bramaderos Project has a porphyry Exploration Target of between 3.3Moz and 8.6Moz AuEq1 w i t h i n 25 5M t t o 36 0 Mt a t a g r a d e b e t w e e n 0. 4 0 a n d 0. 74 g/ t AuEq2, and the Limon epithermal gold -silver Exploration Target of 0.9 - 1.7Moz AuEq within 30Mt - 44Mt at a grade between 0.9 - 1.2g/t AuEq3,4. 1 Refer ASX Announcement on 13 December 2022. 2 The gold equivalent calculation formula for porphyry gold-copper-silver mineralisation at Bramaderos is AuEq(g/t) = (Au grade x Au price x Au recov / 31.1035) + (Ag grade x Ag price x Ag recov / 31.1035) + (Cu grade x Cu price x Cu recov / 100)) / (Au price x Au recov / 31.1035). The prices used were US$1,800/oz gold and US$9,500/t copper and US$22/oz silver. Recoveries are estimated at 89% for gold, 85% for copper, and 60% for silver based on metallurgical studies. In Sunstone’s opinion all the elements included in the metal equivalents calculation have reasonable potential to be recovered and sold. Figure 1: Bramaderos gold in soil contours showing the main porphyry and epithermal domains For personal use only
Page 4
Page 4 of 20 Quarterly Activities Report Period ended 30 September 2025 Limon gold-silver epithermal deposit Located 2.7km northeast of the Brama -Alba-Melonal gold-copper porphyry deposits, t he Limon gold -silver epithermal discovery moved from discovery to Exploration Target in less than ten months. The Limon gold-silver epithermal has an exploration target of between 0.9 and 1.7Moz AuEq within 30 to 44Mt at a grade between 0.9 and 1.2g/t AuEq3,4. Importantly, the higher-grade Limon deposit allows for a scalable, lower capital cost operation to be first built, before developing the much larger porphyry opportunities at Bramaderos. 3 Refer ASX Announcement on 5 February 2024. 4 The gold equivalent calculation formula for the Limon epithermal gold-silver mineralisation is AuEq(g/t) = Au(ppm) + (Ag (ppm)/82). The prices used were US$1,800/oz gold and US$22/oz silver. Recoveries are estimated at over 90% for gold and 90% for silver from metallurgical studies. In Sunstone’s opinion all the elements included in the metal equivalents calculation have reasonable potential to be recovered and sold. Figure 2: Panorama of the valley hosting the Brama and Alba deposits, showing the porphyry systems emerging at surface. The Limon area is behind these hills. For personal use only
Page 5
Page 5 of 20 Quarterly Activities Report Period ended 30 September 2025 Figure 3: The Limon epithermal gold -silver system in plan view, showing multiple mineralised structures in green. High -grade domains are at intersections of NE and WNW trending structures. Recent intersections in holes LMDD048-051 extend mineralisation on the western and eastern sides of the Limon epithermal system. Several additional targets have been defined based on gold- in soil and zinc-in-soil anomalies, and structural interpretation. For personal use only
Page 6
Page 6 of 20 Quarterly Activities Report Period ended 30 September 2025 Copete gold-copper porphyry discovery5 The new Copete gold-copper porphyry discovery is in addition to the previously released Bramaderos Project porphyry Exploration Target of 3.3 – 8.6Moz AuEq within 255Mt to 360Mt at a grade between 0.40 and 0.74g/t AuEq1,2 and therefore presents significant scope for that Bramaderos Exploration Target to be increased. The Copete target remains largely under-explored, with no drilling by Sunstone – but now with a coherent and wide mineralised trench intersection, a 3-D modelled magnetic anomaly plunging to the SE comparable to that seen at Brama and mapped stockwork veining interpreted to represent the upper levels of an intact porphyry system. The Copete discovery means Sunstone has now outlined a 1.8km -long cluster of porphyry gold -copper mineralised intrusions across the Melonal – Copete trend. This trend runs parallel to the Brama-Alba trend and is located only a few hundred meters to the south (see Figure 4). 5 Refer to ASX Announcement on 18 November 2024. Figure 4: Plan map showing the distribution of porphyry gold- copper targets in the immediate vicinity of the Brama-Alba MRE at Bramaderos that are associated with gold anomalism in soil samples (backdrop to image). For personal use only
Page 7
Page 7 of 20 Quarterly Activities Report Period ended 30 September 2025 An updated Mineral Resource to be prepared following completion of a surface sampling program will enable a scoping study to be undertaken at Bramaderos Sunstone’s latest surface sampling exploration program comprising assays received in September 6 and an extensive program completed in October for which assays are pending 7, have returned more strong results which demonstrate the ongoing upside at Bramaderos. Combined with the increase in gold and copper prices (over 100%) since the initial Bramaderos Mineral Resource estimate was published in late 2022, the potential exists for a revised Mineral Resource estimate which may increase the size of the resource to underpin a Scoping Study for the possible multi-decade, large tonnage, low -cost gold -copper mining operations at Bramaderos. As part of this strategy, a significant campaign of surface channel sampling was completed during September at Brama-Alba and on the northeast side of Melonal. This work involved sampling a series of vehicle access roads, drill rig access tracks and ravine s over gold soil anomalies that lie within and adjacent to the 2022 modelled open-pit shell (see Figures 5 and 6). The aims of this work are to: • identify additional zones of mineralisation that lie outside the current resource; • identify if mineralisation is contiguous between Alba and Melonal; • refine the surface geology map and the deposit sub-surface 3D lithology model; • acquire additional samples from surface on the northeast side of Melonal so that a future Mineral resource update can bring part of the area into the resource; and • provide further constraints for detailed vein and alteration modelling of the Brama-Alba deposit. Areas of stockwork veining were encountered along sampling line 5 north of Brama, along sampling lines 6 and 7 between Melonal and Alba, and along parts of sampling line 8 on the south side of Brama (see Figures 5 and 6). Figure 5: Southward-l o o k i n g v i e w o v e r A l b a a n d B r a m a s h o w i n g 4 o f 1 3 s u r f a c e r o c k-sampling lines surrounding the edges of the current resource. 6 Refer to ASX Announcement on 4 September 2025. 7 Refer to ASX Announcement on 14 October 2025. For personal use only
Page 8
Page 8 of 20 Quarterly Activities Report Period ended 30 September 2025 Figure 6: Location of 13 lines of surface rock channel sampling (blue lines) located over soil gold anomalies around the edges of the Brama-Alba resource and within or close to the margins of the planned pit shell as modelled in 2022 (red outline). At Copete, final assays were received from the completed program of ravine rock channel sampling at Copete that covered an area of 400m by 350m (see Figures 7 and 8). An earlier trench at Copete (Trench ML01) yielded 214m @ 0.5 g/t Au-Eq and included 113m @ 0.64 g/t Au-Eq (see ASX announcement dated 12 November 2024). The ravine mapping and sampling at Copete identified two mineralised intrusions that cover an area of 300m by >250m and are strongly stockwork veined. Assays from the first set of ravines (ravines 2 - 6) were announced in an ASX release dated 4 September 2025. Assays from the second set of ravines, QC-1, QC-3Ext, QC-7, QC-11, QC-12 and QC-13, have been received, and significant intersections are listed in Table 1. This work has identified a core zone of higher gold grade in QC-2 and QC-3ext associated with two syn-mineral intrusions, and show that the high-grade mineralisation in Trench ML01 extends downslope to the north and south. This core zone at Copete appears to extend southward towards the Porotillo system. The mineralised quartz diorite porphyry intrusion at Copete is open to the south and extends under cover below the valley floor that lies between Copete and Porotillo. For personal use only
Page 9
Page 9 of 20 Quarterly Activities Report Period ended 30 September 2025 Figure 7: Compilation map showing all sampled ravines at Copete (QC -1 to QC-7 and QC-11 to QC-13) in relation to Trench ML01, which yielded 214m @ 0.50 g/t Au-Equivalent (see ASX announcement dated 12 November 2024). Table 1: Rock channel assay results from the recently completed program at Copete. New assays from ravines QC-1, QC-3ext, QC-7, QC-11, QC-12 and QC-13. For personal use only
Page 10
Page 10 of 20 Quarterly Activities Report Period ended 30 September 2025 There is increasing evidence that the strongest parts of the exposed Copete and Porotillo porphyry systems may be cojoined. They may be part of a 700m -long coherent and tabular mineralised zone that passes under the valley floor that separates Copete from Porotillo (Figure 7). Highly mineralised soil samples along this northeasterly porphyry trend strengthen this interpretation (Figure 8). Figure 8: Overview of the developing geometry and linkage of the Copete and Porotillo porphyry systems. Strong cores of mineralisation at surface at both Copete and Porotillo may be part of a large system whose surface expression is a 700m-long tabular zone that passes under the intervening valley floor. For personal use only
Page 11
Page 11 of 20 Quarterly Activities Report Period ended 30 September 2025 2. El Palmar Copper-Gold Project (Sunstone 74.5%, to acquire 100%) El Palmar is located in northern Ecuador, 60km north -west of Ecuador’s capital, Quito. Under a Staged Acquisition Agreement, Sunstone holds 74.5% and may move to 100% for a payment of US$1.7M by 30 June 2026. El Palmar is made up of five gold-copper porphyry targets, which sit on and around the Toachi fault zone, and also hosts the nearby 2.7Bt Cascabel deposit and the 1Bt Llurimagua deposit. During the December 2024 Quarter, Sunstone announced the inaugural Mineral Resource estimate and initial Exploration Target at El Palmar. Figure 9: Location of the El Palmar and Verde Chico projects relative to the giant Llurimagua, Alpala and Tandayama - America (Cascabel project) porphyry deposits, and the Toachi fault system. Also shown are the concessions held by ENAMI that surround Llurimagua, and which Hanrine (a subsidiary of Hancock Prospecting) have committed to spend US$120 million to earn 49%. For personal use only
Page 12
Page 12 of 20 Quarterly Activities Report Period ended 30 September 2025 El Palmar Mineral Resource Estimate Based on drilling to date at the T1 target at El Palmar, the Company released the inaugural Mineral Resource estimate (MRE) for the T1 target at El Palmar on 22 October 2024 of 64Mt at 0.60g/t AuEq 8,9 (0.41g/t gold, 0.13% copper and 0.7g/t silver) for 1.2Mozs AuEq8,9. Category Tonnage Mt Average Grade Material Content AuEq (g/t) Au (g/t) Ag (g/t) Cu (ppm) Cu (%) AuEq (Koz) Au (Koz) Ag (Koz) Cu (Kt) Indicated 5 0.63 0.42 0.81 1,456 0.15 100 100 100 7 Inferred 59 0.59 0.40 0.65 1,290 0.13 1,100 700 1,200 70 TOTAL 64 0.60 0.41 0.66 1,301 0.13 1,200 800 1,300 80 The MRE is based on 21 drill holes for 17,699m of drilling (18 drilled by Sunstone in the period August 2021 to July 2022 and 3 drilled by Codelco in 2012) and 1,498 linear metres of trenching in 5 trenches. T1, which is at surface, is one of five target gold-copper porphyry deposits at El Palmar, and has the potential to be advanced as a large open pit opportunity before undertaking exploration and development of the deeper 8 Refer ASX Announcement on 22 October 2024. 9 The gold equivalent calculation formula for the El Palmar gold-copper porphyry is AuEq (g/t) = ((Au grade x Au price x Au recov / 31.1035) + (Ag grade x Ag price x Ag recov / 31.1035) + (Cu grade x Cu price x Cu recov / 100)) / (Au price x Au recov / 31.10 35). The prices applied were US$1,800/oz gold, US$4.50/lb copper and US$22/oz silver. Recoveries are estimated at 90% for gold, 78% for copper (excluded for oxide material), and 60% for silver based on metallurgical studies. In Sunstone’s opinion all the elements included in the metal equivalents calculation have reasonable potential to be recovered and sold. Figure 10: El Palmar T1 resource block model for grades >0.2 g/t Au- Eq and pit outline along a 240-060o cross-section and showing the exploration targets which are located within, on the sides, and immediately below the modelled T1 open pit. For personal use only
Page 13
Page 13 of 20 Quarterly Activities Report Period ended 30 September 2025 porphyry opportunities. This MRE establishes a strong platform on which to build a world -scale gold and copper resource inventory at El Palmar. El Palmar Exploration Target In addition to the inaugural MRE, the Company announced an initial Exploration Target for El Palmar of 1.0Bt and 1.2Bt at a grade between approximately 0.3g/t to 0.7g/t gold and approximately 0.1% to 0.3% copper for contained metal of between 10Mozs to 27Mozs gold and 1.0Mt to 3.7Mt copper8. The potential quantity and grade of the Exploration Target is conceptual in nature. There has been insufficient exploration to estimate a Mineral Resource for the target area reported. It is uncertain if further exploration will result in the estimation of a Mineral Resource. The Exploration Target comprises material from the T1, T2 and T3 targets and extends across an area of 1.6km x 1.1km. It includes near-surface mineralisation and deeper mineralisation to depths of 1,500m below surface. The areas of mineralisation captured in the Exploration Target are of high conviction, geologically robust domains consistent with high aspect ratio, clustered porphyry gold-copper deposits. There is potential for the copper content to increase in areas interpreted to be central to the porphyry systems. As the Exploration Target has been estimated from only three of the five target deposits, there is still immense potential to grow at El Palmar, including in the larger untested magnetic anomalies as highlighted in Figure 12. Figure 11: O v e r v i e w o f 9 o f t h e 1 0 exploration targets defined on the El Palmar concession. View is looking at -20 degrees towards azimuth 215o. For personal use only
Page 14
Page 14 of 20 Quarterly Activities Report Period ended 30 September 2025 Verde Chico Project Sunstone is acquiring the Verde Chico Project through a Staged Acquisition Agreement (signed on 23 September 2022). Verde Chico is located to the west of Sunstone’s El Palmar gold-copper porphyry discovery and quadruples Sunstone’s land position to 3,672ha in this prospective belt in northern Ecuador adjacent to the Toachi Fault. The initial exploration activities at Verde Chico have included rock chip sampling and stream sediment sampling programs, along with formal community agreements and environmental baseline surveys. Figure 12: Cross section showing the T2-related Exploration Targets from surface extending to depth to the large T3 target. Note that the MRE and pit are located ‘behind’ this image to the west (refer to Figures 10 & 11). For personal use only
Page 15
Page 15 of 20 Quarterly Activities Report Period ended 30 September 2025 Corporate The Company’s unaudited cash position for 30 September 2025 was approximately A$2.2 million, and the value of tradeable equity investments was approximately A$0 .1 million. The Quarterly Cashflow Report (Appendix 5B) for the period ending 30 September 2025 provides an overview of the Company’s financial activities. Exploration expenditure for the reporting period was A$1.6 million ( June 2025 quarter A$1.5 million) with activities in the current quarter focused on surface soil sampling and mapping activities at Bramaderos to determine potential revisions to the current mineral resource estimate. Corporate and other expenditure (including property, plant, and equipment) amounted to A$0.5 million (March 2025 quarter A$0.7 million). The total amount paid to directors of the entity and their associates in the period (item 6.1 of the Appendix 5B) was A$0.2 million and includes salary, superannuation and directors’ fees. As the Company is an exploration entity, no sales revenue has yet been generated from product sales. Sunstone has primarily funded its activities through the issuance of equity securities. It is expected that the Company will be able to fund its future acti vities through further issuances of equity securities and consideration of corporate and project-level strategic partnerships. Shareholder Information Issued Shares ASX: STM Opening balance 30 June 2025 6,084,259,486 Performance rights vested 12,000,000 Options exercised 211,855,190 Closing balance at 30 September 2025 6,308,114,676 Subsequent to 30 September 2025, a further 39 million options have been converted to shares at a strike price of $0.0075 (amounting to $0.3 million in proceeds) . These options had been issued to subscribers in the September 2024 Placement and October 2024 Share Purchase Plan. There remain a further 259 million in-the-money options, with a value of $1.9 million, still to be exercised. For any shareholders who would like to enquire about the process to convert options to shares, please email info@sunstonemetals.com.au. For personal use only
Page 16
Page 16 of 20 Quarterly Activities Report Period ended 30 September 2025 Notes Specific – September 2025 Quarter ASX Announcements The following announcements, which relate to information in this Quarterly Report, were lodged with the ASX. Further details (including JORC 2012 Code Reporting Tables, where applicable) for the results summarised above can be found in the announcements: Sunstone targeting an updated Mineral Resource 14 October 2025 Application for quotation of securities 8 October 2025 Application for quotation of securities 30 September 2025 Change in Substantial Holding 22 September 2025 Application for quotation of securities 22 September 2025 Change in Director’s Interest Notice 16 September 2025 S708A(5) Cleansing Notice 16 September 2025 Notification of cessation of securities – STM 16 September 2025 Application for quotation of securities – STM 16 September 2025 Appendix 4G 12 September 2025 Annual Report to shareholders 12 September 2025 Application for quotation of securities 5 September 2025 Assays highlight scope for Bramaderos resource growth 4 September 2025 Application for quotation of securities 27 August 2025 Application for quotation of securities 21 August 2025 Application for quotation of securities 13 August 2025 Application for quotation of securities 5 August 2025 Quarterly Activities/Appendix 5B Cash Flow Report 31 July 2025 Application for quotation of securities 28 July 2025 Presentation Noosa Mining Conference 24 July 2025 Results of Meeting 22 July 2025 Application for quotation of securities 21 July 2025 Application for quotation of securities 14 July 2025 Application for quotation of securities 7 July 2025 For personal use only
Page 17
Page 17 of 20 Quarterly Activities Report Period ended 30 September 2025 Tenement Schedule At the end of the quarter, the Company holds the following tenements: Gold-copper tenements - Ecuador Tenement Holder Tenement Name Location Status Sunstone Ownership Bramaderos S.A. BramaderosA Loja, Ecuador Granted 87.5% Bramaderos S.A. Bramaderos 02 Loja, Ecuador Granted 87.5% Bramaderos S.A. Cueva de Leon Loja, Ecuador Granted 87.5% Golden Exploration Ecuador S.A. Los Mandariyacus (El Palmar)B Imbabura, Ecuador Granted 74.5%B Compania Minera Verde Chico CIA Ltda Verde ChicoC Imbabura, Ecuador Granted 0% Notes A: Sunstone announced on 7 January 2020 that the terms of the Earn -in Joint Venture with TSX -V listed Cornerstone Capital Resources (subsequently merged with SolGold PLC) had been amended to provide Sunstone with an immediate 87.5% interest and SolGold wi th a loan carried 12.5% interest in Bramaderos S.A. (formerly named La Plata Minerales S.A.) the holder of the Bramaderos concession. B: Sunstone announcement 12 August 2020 regarding a Staged Acquisition Agreement for 100% of the El Palmar project. Sunstone currently holds 74.5% and can acquire the remaining 25.5% by 30 June 2026. C: Sunstone announcement 21 June 2022 regarding a Letter of Intent to acquire 100% of the Verde Chico Project, located to the west of Sunstone’s El Palmar gold-copper porphyry discovery in northern Ecuador, through a Staged Acquisition Agreement, signed 23 September 2022, from the Verde Chico Group. Competent Persons Statement The information in this report that relates to exploration results and Exploration Targets is based upon information reviewed by Dr Bruce Rohrlach who is a Member of the Australasian Institute of Mining and Metallurgy. Dr Rohrlach is a full-time employee of Sunstone Metals Ltd and has sufficient experience which 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”. Dr Rohrlach consents to the inclusion in the report of the matters based on his information in the form and context in which it appears. The information relating to the Bramaderos Mineral Resource is extracted from the ASX announcement on 13 December 2022. The information relating to the El Palmar Mineral Resource is extracted from the ASX announcement on 22 October 2024. The company confirms that it is not aware of any new information or data that materially affects the information included in the original market announcements and that all material assumptions and technical parameters underpinning the estimates in the relevant market announcements continue to apply and have not materially changed. The company confirms that the form and context in which the Competent Person’s findings are presented for their respective Mineral Resource estimates have not been materially modified from the original market announcements. For personal use only
Page 18
Page 18 of 20 Quarterly Activities Report Period ended 30 September 2025 Information on Exploration Targets Bramaderos The Bramaderos porphyry Exploration Target within the Bramaderos concession is estimated from 3 areas – the extensions to the Brama-Alba system that are not captured in the Mineral Resource estimate (MRE), and mineralisation drilled at the targets of Melonal and Limon porphyry mineralisation. The Exploration Target does not include known porphyry mineralisation at Sandia, Porotillo, Playas, Copete or Yeso. It was decided to not include these areas because Sunstone has not yet completed any or sufficient drilling in these areas. Some historical drilling has been completed at Porotillo. Further work in these areas will be undertaken and they are expected to contribute to an expanded Exploration Target in future. Several areas of mineralisation have been identified outside of the area of the MRE. The MRE captured all material within a ‘Mineralisation Wireframe’, and within an economically modelled pit. Some drill holes that intersected mineralisation are outside t he mineralisation wireframe, and either within or outside the pit. Inadequate drilling exists in these areas to show continuity. Furthermore, the effect of the reasonable prospects of economic extraction was to exclude 14% of material. This material has be en captured in the Exploration Target. Six domains were identified as having clear potential for additional mineralisation and these were reviewed either on a depth slice basis, or a block basis. Volumes were calculated and grade was assigned based on nearby data and on comparison with the overall Brama-Alba grade. The Melonal target is a continuation of the Br ama-Alba system. It is geologically grouped with Brama- Alba. Recent drilling by Sunstone, and historical drilling from 2007, has confirmed that the Melonal target is mineralised, and that mineralisation is host ed in rocks the same as those drilled at the nearby Brama -Alba deposit. The mineralised rocks are coincident with a discrete sub -vertical magnetic anomaly measuring up to 400m in diameter, and with a vertical extent of over 1,000m. The Exploration Target for Melonal was considered to a depth of 500m. The Melonal target straddles the approved Bramaderos -01 and Bramaderos -02 concessions. Sunstone has drilled 8 effective diamond holes at the Limon porphyry target. Mineralisation has been intersected in a number of holes. A trench (LM_TR_01) was completed at Limon prior to drilling in an area of outcropping stockwork veining and minor second ary copper mineralisation. It returned 97m at 0.73g/t gold and 0.23% copper. A recent hole drilled under the trench has intersected similar stockwork veined intrusive and contains chalcopyrite. This area around Trench TR_LM_01 has been included in the porphyry Exploration Target where more drilling is required to allow inclusion in a Mineral Resource estimate. This target area will be further explored with drilling programs to be executed over the next two years, subject to the Company’s funding ability. Limon epithermal The Limon epithermal Exploration Target was estimated on target prospects where there was a combination of diamond drilling (by Sunstone), geological mapping, trenching, geochemistry (soils) and to a lesser extent geophysical data (magnetics) which could support the geological and mineralisation concept model. The Limon alteration area has been covered with soil sampling on a 50m x 50m grid. This survey is an important exploration method which identified several gold-in soil anomalies that are primary targets for drilling. The soil geochemical data is further interpreted using related element associations typical of epithermal systems, such as areas of somewhat coincident gold, silver, zinc, lead, copper, tellurium and arsenic. Target areas have also been strengthened using alteration mineralogy from a hand -held Terraspec instrument. These data assist in mapping the alteration zones most likely to be associated with epithermal mineralisation. For personal use only
Page 19
Page 19 of 20 Quarterly Activities Report Period ended 30 September 2025 Drilling at Limon has also intersected a high sulphidation system in holes LMDD004 and 006, which included intersections of 13.3m at 0.43% copper and 0.11g/t gold, within 59.6m at 0.16% copper. Standard geological mapping and rock chip sampling has also been undertaken across the Limon target area. The volume ranges for the initial Exploration Target in the Central Shoot were estimated using cross sections and 3 -D modelling in Leapfrog software, based upon an analysis of drilling, mineralised rock types, grade distribution, potential for extrapolation of mineralisation continuity and interpreted geological risk. The volume ranges for the other components were estimated from geological interpretation and guided by extent of surface geochemical anomalism, supplemented by preliminary drilling. A conservative approach was taken to the potential distribution of gold and silver bearing veins. This target area will be further explored with drilling programs to be executed over the next two years, subject to the Company’s funding ability. El Palmar The Exploration Target within the El Palmar concession is estimated from within the T1, T2 and T3 areas. The Exploration Target does not include interpreted or known porphyry mineralisation at the T4 and T5 target areas. It was decided to not include these areas because Sunstone has not yet completed any drilling at T4 and has conducted only minor drilling at T5. Further work in these areas will be undertaken and they are expected to contribute to an expanded Exploration Target in future. The components of the exploration target are based on a combination of diamond drilling conducted by Codelco (during 2012) and by Sunstone (during 2022 and 2023), ground magnetics, multi -element soil sampling, multi-element rock chip and channel sampling, mulit-element trench sampling and deep magnetic inversion anomalies modelled from ground magnetic data. Wireframes of the areas within the Exploration Target areas were created in Leapfrog software using data interpreted from the Mineral Resource block model, iso-surface contours of modelled magnetic intensities, and grade ranges in available diamond drill h oles. The volumes were multiplied by a specific gravity of 2.72g/cc (the average density of the T1 resource) to determine the tonnage range of the target. Grade ranges were determined with reference to drill intersection and surface rock chip assays. The next step in testing these targets is primarily diamond drill testing. The targets have been adequately defined, but drill programs still require detailed planning regarding the number of drill holes, their azimuths, dips, and final depths. Drilling of these targets will be undertaken over the next two years, subject to the company's funding availability. For personal use only
Page 20
Page 20 of 20 Quarterly Activities Report Period ended 30 September 2025 Directory Sunstone Metals Limited ABN 68 123 184 412 Website www.sunstonemetals.com.au Email info@sunstonemetals.com.au Stock exchange listing Australian Stock Exchange ASX Code: STM Investor Information Contacts Lucas Welsh – Company Secretary Sunstone Metals Limited Phone: 03 7044 2627 Email: info@sunstonemetals.com.au Shareholder Enquiries Registered office Share registry matters should be directed to: Level 31, 120 Collins St Melbourne Victoria 3000 Phone: 03 7044 2627 Computershare Investor Services Phone: 1300 850 505 Website: www.computershare.com.au Issued capital At 30 September 2025: Ordinary shares: 6,308,114,676 (STM) Unlisted Performance Rights: 148,176,005 (STMAS) Unlisted Options: 316,288,959 (STMAL) Directors (as at 30 September 2025) Company Secretary Malcolm Norris – Non-Executive Chairman Patrick Duffy – CEO & Managing Director Neal O’Connor – Non-Executive Director Stephen Stroud – Non-Executive Director Lucas Welsh For further information please visit www.sunstonemetals.com.au or contact: Sunstone Metals Limited T: 03 7044 2627 E: info@sunstonemetals.com.au www.sunstonemetals.com.au For personal use only
Page 21
Rule 5.5 ASX Listing Rules Appendix 5B (17/07/20) Page 1 + See chapter 19 of the ASX Listing Rules for defined terms. Appendix 5B Mining exploration entity or oil and gas exploration entity quarterly cash flow report Name of entity SUNSTONE METALS LIMITED ABN Quarter ended (“current quarter”) 68 123 184 412 30 SEPTEMBER 2025 Consolidated statement of cash flows Current quarter $A’000 Year to date (3 months) $A’000 1. Cash flows from operating activities 1.1 Receipts from customers 1.2 Payments for (a) exploration & evaluation (b) development (c) production (d) staff costs (173) (173) (e) administration and corporate costs (374) (374) 1.3 Dividends received (see note 3) 1.4 Interest received 12 12 1.5 Interest and other costs of finance paid 1.6 Income taxes paid 1.7 Government grants and tax incentives 1.8 Other (provide details if material) 9 9 1.9 Net cash from / (used in) operating activities (526) (526) 2. Cash flows from investing activities 2.1 Payments to acquire or for: (a) entities (b) tenements (c) property, plant and equipment (2) (2) (d) exploration & evaluation (1,576) (1,576) (e) investments (f) other non-current assets For personal use only
Page 22
Appendix 5B Mining exploration entity or oil and gas exploration entity quarterly cash flow report ASX Listing Rules Appendix 5B (17/07/20) Page 2 + See chapter 19 of the ASX Listing Rules for defined terms. Consolidated statement of cash flows Current quarter $A’000 Year to date (3 months) $A’000 2.2 Proceeds from the disposal of: (a) entities (b) tenements (c) property, plant and equipment (d) investments (e) other non-current assets 2.3 Cash flows from loans to other entities 2.4 Dividends received (see note 3) 2.5 Other (provide details if material) 2.6 Net cash from / (used in) investing activities (1,578) (1,578) 3. Cash flows from financing activities 3.1 Proceeds from issues of equity securities (excluding convertible debt securities) 3.2 Proceeds from issue of convertible debt securities 3.3 Proceeds from exercise of options 1,679 1,679 3.4 Transaction costs related to issues of equity securities or convertible debt securities (31) (31) 3.5 Proceeds from borrowings 3.6 Repayment of borrowings 3.7 Transaction costs related to loans and borrowings 3.8 Dividends paid 3.9 Other (provide details if material) 3.10 Net cash from / (used in) financing activities 1,648 1,648 4. Net increase / (decrease) in cash and cash equivalents for the period 4.1 Cash and cash equivalents at beginning of period 2,675 2,675 4.2 Net cash from / (used in) operating activities (item 1.9 above) (526) (526) 4.3 Net cash from / (used in) investing activities (item 2.6 above) (1,578) (1,578) 4.4 Net cash from / (used in) financing activities (item 3.10 above) 1,648 1,648 For personal use only
Page 23
Appendix 5B Mining exploration entity or oil and gas exploration entity quarterly cash flow report ASX Listing Rules Appendix 5B (17/07/20) Page 3 + See chapter 19 of the ASX Listing Rules for defined terms. Consolidated statement of cash flows Current quarter $A’000 Year to date (3 months) $A’000 4.5 Effect of movement in exchange rates on cash held - - 4.6 Cash and cash equivalents at end of period 2,219 2,219 5. Reconciliation of cash and cash equivalents at the end of the quarter (as shown in the consolidated statement of cash flows) to the related items in the accounts Current quarter $A’000 Previous quarter $A’000 5.1 Bank balances 2,219 2,219 5.2 Call deposits 5.3 Bank overdrafts 5.4 Other (provide details) 5.5 Cash and cash equivalents at end of quarter (should equal item 4.6 above) 2,219 2,219 6. Payments to related parties of the entity and their associates Current quarter $A'000 6.1 Aggregate amount of payments to related parties and their associates included in item 1 151 6.2 Aggregate amount of payments to related parties and their associates included in item 2 Note: if any amounts are shown in items 6.1 or 6.2, your quarterly activity report must include a description of, and an explanation for, such payments. 7. Financing facilities Note: the term “facility’ includes all forms of financing arrangements available to the entity. Add notes as necessary for an understanding of the sources of finance available to the entity. Total facility amount at quarter end $A’000 Amount drawn at quarter end $A’000 7.1 Loan facilities 7.2 Credit standby arrangements 7.3 Other (please specify) 7.4 Total financing facilities 7.5 Unused financing facilities available at quarter end 0 7.6 Include in the box below a description of each facility above, including the lender, interest rate, maturity date and whether it is secured or unsecured. If any additional financing facilities have been entered into or are proposed to be entered into after quarter end, include a note providing details of those facilities as well. For personal use only
Page 24
Appendix 5B Mining exploration entity or oil and gas exploration entity quarterly cash flow report ASX Listing Rules Appendix 5B (17/07/20) Page 4 + See chapter 19 of the ASX Listing Rules for defined terms. 8. Estimated cash available for future operating activities $A’000 8.1 Net cash from / (used in) operating activities (item 1.9) (526) 8.2 (Payments for exploration & evaluation classified as investing activities) (item 2.1(d)) (1,576) 8.3 Total relevant outgoings (item 8.1 + item 8.2) (2,102) 8.4 Cash and cash equivalents at quarter end (item 4.6) 2,219 8.5 Unused finance facilities available at quarter end (item 7.5) 0 8.6 Total available funding (item 8.4 + item 8.5) 2,219 8.7 Estimated quarters of funding available (item 8.6 divided by item 8.3) 1.1 Note: if the entity has reported positive relevant outgoings (ie a net cash inflow) in item 8.3, answer item 8.7 as “N/A”. Otherwise, a figure for the estimated quarters of funding available must be included in item 8.7. 8.8 If item 8.7 is less than 2 quarters, please provide answers to the following questions: 8.8.1 Does the entity expect that it will continue to have the current level of net operating cash flows for the time being and, if not, why not? Answer: Yes. 8.8.2 Has the entity taken any steps, or does it propose to take any steps, to raise further cash to fund its operations and, if so, what are those steps and how likely does it believe that they will be successful? Answer: As a junior explorer the Company is at all times considering opportunities for funding its business, including corporate investment opportunities. The Company has a track record of successfully raising funds to deliver discoveries and expects to be able to fund the planned activities outlined in the Quarterly Report. 8.8.3 Does the entity expect to be able to continue its operations and to meet its business objectives and, if so, on what basis? Answer: Yes – it is expected that the Company will be able to fund its future activities through the continued exercise of in-the-money options by option holders, further issuances of equity securities, and consideration of project and asset-level strategic partnerships/investments. Note: where item 8.7 is less than 2 quarters, all of questions 8.8.1, 8.8.2 and 8.8.3 above must be answered. Compliance statement 1 This statement has been prepared in accordance with accounting standards and policies which comply with Listing Rule 19.11A. 2 This statement gives a true and fair view of the matters disclosed. Date: 31 October 2025 ................................................................................... Authorised by: Lucas Welsh – Company Secretary ................................................................................. (Name of body or officer authorising release – see note 4) Notes 1. This quarterly cash flow report and the accompanying activity report provide a basis for informing the market about the entity’s activities for the past quarter , how they have been financed and the effect this has had on its cash position. An For personal use only
Page 25
Appendix 5B Mining exploration entity or oil and gas exploration entity quarterly cash flow report ASX Listing Rules Appendix 5B (17/07/20) Page 5 + See chapter 19 of the ASX Listing Rules for defined terms. entity that wishes to disclose additional information over and above the minimum required under the Listing Rules is encouraged to do so. 2. If this quarterly cash flow report has been prepared in accordance with Australian Accounting Standards, the definitions in, and provisions of, AASB 6: Exploration for and Evaluation of Mineral Resources and AASB 107: Statement of Cash Flows apply to this report. If this quarterly cash flow report has been prepared in accordance with other accounting standards agreed by ASX pursuant to Listing Rule 19.11A, the corresponding equivalent standards apply to this report. 3. Dividends received may be classified either as cash flows from operating activities or cash flows from investing activities, depending on the accounting policy of the entity. 4. If this report has been authorised for release to the market by your board of directors, you can insert here: “By the board”. If it has been authorised for release to the market by a committee of your board of directors, you can insert here: “By the [name of board committee – eg Audit and Risk Committee] ”. If it has been authorised for release to the market by a disclosure committee, you can insert here: “By the Disclosure Committee”. 5. If this report has been authorised for release to the market by your board of directors and you wish to hold yourself out as complying with recommendation 4.2 of the ASX Corporate Governance Council’s Corporate Governance Principles and Recommendations, the board should have received a declaration from its CEO and CFO that, in their opinion, the financial records of the entity have been properly maintained, that this report complies with the appropriate accounting standards and gives a true and fair view of the cash flows of the entity, and that their opinion has been formed on the basis of a sound system of risk management and internal control which is operating effectively. For personal use only