Announcement PDF 1 ASX ANNOUNCEMENT ASX: VTX 11 September 2026 AMENDMENT TO UPDATED MINERAL RESOURCE ESTIMATE — REWARD GOLD MINE, HILL END Amendment to previous announcement This announcement is an amendment to the announcement titled “Updated Mineral Resource Estimate – Reward Gold Mine, Hill End”, lodged on 2 September 2026 by Vertex Minerals Limited (ASX: VTX) (“Vertex” or “the Company”) (the “Original Announcement”). ASX Listing Rule 5.8.1 The Original Announcement did not comply with ASX Listing Rule 5.8.1. Specifically, it did not include in the body of the Original Announcement a fair and balanced representation of the information contained in the report prepared under ASX Listing Rule 5.8.2, including a summary of all information material to understanding the reported estimates of Mineral Resources in relation to the matters set out in Listing Rule 5.8.1. This detailed information was set out in JORC Code (2012) Table 1. ASX Listing Rule 5.8.1 requires that JORC Code (2012) Table 1 is summarised in the body of the announcement. The information required by Listing Rule 5.8.1 is now set out in the body of this amended Original Announcement under the heading “Summary of information material to understanding the Mineral Resource Estimate (ASX Listing Rule 5.8.1)”. The JORC Code (2012) Table 1 report required by ASX Listing Rule 5.8.2 continues to be appended to the amended Original Announcement. Extent of the Changes Other than the addition of this cover page and the Listing Rule 5.8.1 summary described above, the content of the Original Announcement is unchanged. The Mineral Resource estimate is unchanged: the Reward Gold Mine Mineral Resource remains 274,000 tonnes at 16.68 g/t Au for 146,900 ounces of contained gold at a 4.0 g/t Au lower cut-off, comprising an Indicated Mineral Resource of 80,000 tonnes at 21.17 g/t Au for 54,700 ounces and an Inferred Mineral Resource of 194,000 tonnes at 14.76 g/t Au for 92,200 ounces. This amended announcement supersedes the Original Announcement in its entirety and should be read in its place. This announcement has been approved for release to the ASX by the Directors of Vertex Minerals Limited. 2 ASX ANNOUNCEMENT ASX: VTX 2 September 2026 UPDATED MINERAL RESOURCE ESTIMATE REWARD GOLD MINE, HILL END — "Reward Resource Re-estimated at 146,900oz (16.68 g/t Au); Indicated Grade Up 36% to 21.17 g/t Au on Tighter Geological Model" 2023 MRE reassessed with detailed review which defines priority underground drill targets; no material change to the current mine plan HIGHLIGHTS ● Updated Mineral Resource Estimate (MRE) for the Reward Gold Mine completed by independent consultants HGS Australia in accordance with the JORC Code (2012): 274,000 tonnes at 16.68 g/t Au for 146,900 ounces at a 4.0 g/t Au lower cut-off. ● Indicated Mineral Resource of 80,000 tonnes at 21.17 g/t Au for 54,700 ounces — an increase in Indicated grade of 36% over the June 2023 Indicated grade of 15.54 g/t Au. ● The proportion of contained ounces classified as Indicated has risen from 31% to 37%, reflecting improved geological confidence from mine reconciliation, underground mapping and development exposure. ● Overall Resource grade is effectively unchanged at 16.68 g/t Au (June 2023: 16.72 g/t Au), confirming the high-grade character of the deposit ● Total contained ounces have decreased by 35% from the 225,200 ounces reported in June 2023 (ASX announcement 21 June 2023). The reduction is attributable to two factors, described in detail below: ○ the application of a 200 g/t Au top-cut to a small number of extreme outlier assays, which the Competent Person considers necessary to avoid over-estimation of grade in a coarse-gold system; and ○ a reduction in the number and size of interpreted lodes following mine reconciliation, underground mapping and mine development, and recognition of the controlling structures, where certain lodes no longer meet the JORC Code requirement for reasonable prospects for eventual economic extraction. ● Reported on an uncut basis, the estimate would be 276,000 tonnes at 21.57 g/t Au for 192,000 ounces. The difference demonstrates the material influence of a small number of very high-grade samples, and the Company has elected to report the more conservative top-cut estimate. ● There is no material change to the current mine plan, to the underground development schedule, or to the Company's plan to bring the Reward Gold Mine to full production from October 2026. The lodes currently being developed and stoped are unaffected. ● The re-interpretation has defined three priority underground drill target areas: depth extensions below the existing Resource; remnant ultra-high-grade material in and around the historic Hawkins Hill mine directly above Reward; and along strike to the south at Fosters. ● The Fosters Exploration Target previously reported by the Company (ASX announcement 29 August 2023) is unchanged by this estimate: 524,000 tonnes at 12.5 g/t Au for 211,000 ounces (lower range) to 524,000 tonnes at 19.0 g/t Au for 321,000 ounces (upper range). Refer to the cautionary statement under “Fosters Exploration Target” below. ● Vertex plans to drill Fosters, which sits down strike to the south of, and below, the Reward Gold Mine. Fosters will be accessed via the existing Fosters adit, which is only a few hundred metres down strike from the Hill End gravity gold plant. ● Underground diamond drilling is planned to commence in the first quarter of 2027. The move to 24-hour underground operations approved on 20 August 2026 provides the operational capacity to establish a dedicated underground drilling team 3 Overview Vertex Minerals Limited (ASX: VTX) (“Vertex” or “the Company”) advises that it has completed a review of the 2023 Mineral Resource Estimate for the Reward Gold Mine at its 100%-owned Hill End Gold Project in the Lachlan Fold Belt, NSW. The estimate was prepared by independent consultants HGS Australia in accordance with the 2012 Edition of the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC Code). The June 2023 estimate was prepared before Vertex recommenced mining at Reward. Since that time the Company has recommenced mining and has completed extensive underground mapping and face sampling, substantial underground development that has physically exposed the mineralised structures, and — critically — reconciliation of material actually mined and processed against the modelled tonnes and grade. This work has materially improved the geological understanding of the deposit, and the updated estimate reflects that improved understanding rather than any change in the underlying gold endowment of the Hill End field. The result is a smaller but better-defined and higher-confidence domained resource, with a significantly higher Indicated grade and a clearer structural framework from which to target future drilling. Updated Mineral Resource Estimate Classification Cut-off (g/t Au) Tonnes Au (g/t) Contained Au (oz) Indicated 4.0 80,000 21.17 54,700 Inferred 4.0 194,000 14.76 92,200 Total 4.0 274,000 16.68 146,900 Table 1: Reward Gold Mine Mineral Resource Estimate, August 2026 (200 g/t Au top-cut, 4.0 g/t Au lower cut-off). Figures are rounded and may not sum exactly. Mineral Resources are reported inclusive of any Ore Reserves; the Company has not declared an Ore Reserve for the Reward Gold Mine. Comparison with the June 2023 estimate Classification June 2023 (oz) August 2026 (oz) Change (oz) Change (%) Indicated 70,500 54,700 -15,800 -22% Inferred 154,700 92,200 -62,500 -40% Total 225,200 146,900 -78,300 -35% 4 Classification June 2023 (oz) August 2026 (oz) Change (oz) Change (%) Indicated grade (g/t Au) 15.54 21.17 +5.63 +36% Total grade (g/t Au) 16.72 16.68 -0.04 0% Table 2: Comparison of the August 2026 Mineral Resource Estimate with the estimate reported on 21 June 2023. Both estimates are reported at a 4.0 g/t Au lower cut-off. Reasons for the change Mine reconciliation The single most significant change since June 2023 is that waste grades have been included in the block model waste blocks in the waste outside the vein (0.18m wide) in the minimum mining width of 1m. Reward is now an operating mine. Vertex has developed through the orebody, stoped from it and processed the material through the Gekko gravity plant, and has been able to reconcile the tonnes and grade actually delivered against the tonnes and grade the resource model predicted. Reconciliation of this kind is the most direct test available of a resource model. It measures the model against physical production rather than against further estimation, and where the two diverge it identifies precisely which lodes and which areas of the model are not performing as interpreted. That information is not obtainable from drilling alone, and it is the principal reason the Competent Person has been able to constrain the 2026 interpretation with materially greater confidence than was possible in 2023. Re-interpretation of lodes and controlling structures Vertex has conducted extensive mine reconciliation, underground mapping, underground mine development work and recognition of the controlling structures In practical terms, physical access to the orebody has allowed the Company to see the structures directly and help better domaining. Several lodes interpreted in 2023 have been shown to be narrower, shorter or less continuous than modelled, and have been reduced or removed from the estimate. Conversely, the lodes that remain are better constrained are showing better reconciliation to milled grades. Underground face sampling and further re-interpretation The Competent Person has identified that a number of the more recent underground face samples do not fall within the currently interpreted lode wireframes. A full re-interpretation of the lode geometry incorporating this face sampling data is required has been completed internally but needs further independent assessment. Investors should note that this further re-interpretation may result in changes to the Mineral Resource Estimate, in either direction. The Company will report the outcome of that work to the market in accordance with its continuous disclosure obligations. Implications for the mine plan The updated estimate does not result in any material change to the Company's current mine plan or to the underground development and production schedule previously reported. The lodes presently being developed and stoped — including the Mica Lense currently being mined from Decline 3 by mechanised longhole open stoping The Company has not declared an Ore Reserve for the Reward Gold Mine. Statements in this announcement concerning the mine plan, development schedule and future production are forward looking and are not based on an Ore Reserve estimate. Refer to the Forward- Looking Statements notice at the end of this announcement. Where this points the drill: three priority target areas A principal objective of this work was to establish where Vertex should target future underground drilling at Reward. The improved structural model has defined three priority areas: 1. Depth extensions below the existing Resource The Reward lodes remain open at depth. The recognition of the controlling structures provides, for the first time, a predictive framework for where those lodes should project below the currently modelled limits of the Resource. Historic mining across the Hill End field rarely extended below the water table at approximately 60 feet (less than 20 metres), and only a limited portion of the strike has been drilled to any significant depth. 5 2. Hawkins Hill remnants in the upper levels The historic Hawkins Hill mine sits directly above the Reward workings and is among the highest-grade gold mines recorded in Australia. The upper levels of the Vertex workings provide access to remnant material in and around those historic stopes — blocks left behind by nineteenth-century mining methods that were unable to recover them selectively. The structural work completed for this estimate improves the Company's ability to locate those remnants from underground drill platforms. Historic production figures for the Hawkins Hill mine are historical records and are not reported as a Mineral Resource or Exploration Target under the JORC Code. They are not necessarily indicative of the results that may be achieved at Reward. 3. Down strike to the south at Fosters Fosters lies approximately 400 metres south of the Reward Gold Mine, sitting down strike to the south of and below the Reward workings on the same structural corridor. It falls within ground already covered by Vertex Mining Licences and existing Development Consent. Fosters is accessed via the existing Fosters adit and development drive. The adit is only a few hundred metres down strike from the Hill End gravity gold plant, meaning any material subsequently mined at Fosters would have a very short haul to existing processing infrastructure. No new approvals are required to test Fosters from underground. Fosters Exploration Target The Exploration Target previously reported by the Company for Fosters (ASX announcement 29 August 2023) is unchanged by this Mineral Resource Estimate and remains current. It was estimated by HGS Australia and is reported in accordance with clause 17 of the JORC Code (2012). Range Tonnes Au (g/t) Contained Au (oz) Lower range 524,000 12.5 211,000 Upper range 524,000 19.0 321,000 Table 3: Fosters Exploration Target, as reported on 29 August 2023 and unchanged. The Exploration Target relates to the Amalgamated Lode only and assumes a single lode to a maximum width of one metre; the estimate applies a bulk density of 2.7 t/m³ derived from the Reward resource estimate, with 30% of the lode assigned a grade range of 30–40 g/t Au and the remaining 70% a grade range of 5–10 g/t Au. Multiple parallel lodes are identifiable in the surface topography but are not included in the estimate. The potential quantity and grade of the Exploration Target is conceptual in nature. There has been insufficient exploration to define a Mineral Resource at Fosters, and it is uncertain whether further exploration will result in the determination of a Mineral Resource. The Exploration Target is not being reported as part of any Mineral Resource or Ore Reserve estimate. Underground drilling programme Vertex plans to commence underground diamond drilling at Reward in the first quarter of 2027. The approval for 24-hour underground operations granted by Bathurst Regional Council on 20 August 2026 (ASX announcement 20 August 2026) is central to this. Available working hours at the mine increase from approximately 9 hours per day to up to 22 hours per day. That additional development capacity allows the Company to cut dedicated drill cuddies and platforms underground without displacing ore development from the production schedule — something that has not been practical under the previous restricted operating hours. Drilling from underground platforms is materially more effective than surface drilling at Reward: holes are shorter, better oriented to the steeply dipping lodes, and can be positioned to test the depth extensions, the Hawkins Hill remnants and the Fosters corridor from close range. Drilling at Fosters Vertex plans to drill Fosters as part of this programme. Fosters sits down strike to the south of and below the Reward Gold Mine and will be accessed via the existing Fosters adit, a few hundred metres down strike from the Hill End gravity gold plant. Because the adit and development drive are already in place and the ground is covered by existing Mining Licences and Development Consent, the target can be drilled without new approvals or new surface disturbance. The objective of drilling at Fosters is to test the Exploration Target described above with the aim of converting some or all of it to a Mineral Resource. There is no certainty that drilling will result in the determination of a Mineral Resource at Fosters. 6 Hill End & Hargraves Project Mineral Resource Estimate Deposit Classification Tonnes (kt) Au (g/t) Contained Au (koz) Reward Gold Mine Indicated 80 21.2 55 Inferred 194 14.8 92 Sub Total 274 16.7 147 Hargraves Project Indicated 1,109 2.7 97 Inferred 1,210 2.1 80 Sub Total 2,319 2.4 178 Red Hill Project Indicated 413 1.4 19 Inferred 1,063 1.8 61 Sub Total 1,476 1.7 80 Project Total Indicated 1,602 3.3 171 Inferred 2,467 2.9 233 Grand Total 4,069 3.1 404 Table 4: Global Mineral Resource Estimate for the Hill End & Hargraves Gold Project incorporating the updated Reward estimate. Hargraves and Red Hill figures are unchanged from those reported on 21 June 2023. Figures are rounded and may not sum exactly. Summary of information material to understanding the Mineral Resource Estimate (ASX Listing Rule 5.8.1) The following summary is provided in accordance with ASX Listing Rule 5.8.1. It is intended to be a fair and balanced representation of the information contained in the JORC Code (2012) Table 1 report appended to this announcement under ASX Listing Rule 5.8.2. Where a matter is dealt with in greater technical detail in Table 1, that detail is not repeated here. Geology and geological interpretation The Reward Gold Mine lies within the Hill End goldfield in the Hill End Trough, on the eastern margin of the Lachlan Fold Belt in central New South Wales. Mineralisation occurs as a series of stacked, steeply dipping quartz vein systems (lodes) hosted within Devonian turbidite sequences. Gold occurs as coarse, free, nuggety gold within the quartz veins, with negligible sulphide content. The estimated block model extends from 6,341,000mN to 6,341,800mN, from 725,220mE to 725,400mE, and from 550mRL to 1,002mRL (GDA2020, Zone 55). The 2026 geological interpretation is materially better constrained than the June 2023 interpretation. Since 2023, Vertex has recommenced mining, completed extensive underground mapping and face sampling, driven development that physically exposes the mineralised structures, recognised the controlling reverse-fault and vein-intersection structures, and reconciled material mined and processed against the tonnes and grade predicted by the model. That work has allowed the lode wireframes to be re-domained with greater confidence. Several lodes interpreted in 2023 have been demonstrated to be narrower, shorter or less continuous than modelled, and have been reduced in size or removed from the estimate where they do not meet the JORC Code requirement of reasonable prospects for eventual economic extraction. The lodes that remain are better constrained and reconcile more closely to milled grades. The Competent Person has identified that a number of the more recent underground face samples fall outside the currently interpreted lode wireframes. A full re-interpretation of lode geometry incorporating that data is required and is planned, and may result in further change to the Mineral Resource Estimate in either direction. The Company will report the outcome of that work to the market in accordance with its continuous disclosure obligations. Sampling and sub-sampling techniques Three sampling methods underpin the estimate. Diamond core was half-cored by diamond saw down the structural long axis, with the same relative portion of core sampled for each interval and sample lengths varied to honour vein thickness; a few centimetres of wall rock either side of the vein were routinely included so that the footwall and hanging wall contacts were captured. Reverse circulation samples were collected over 1m intervals through a cyclone and split to approximately 3kg, although no reverse circulation interval intersected the mineralisation reported here. Underground face sampling comprises approximately 8kg of representative quartz vein material collected by a geologist across true width from footwall to hanging 7 wall, with separate samples taken where two or more veins are present in a face. Faces are spaced at approximately 1.75m and generally every second face is sampled, giving an effective sample spacing of approximately 3.5m along development. For screen fire assay, each sample was weighed, dried and pulverised in its entirety in an LM2 to 85% passing 75 microns. For Leachwell digestion, approximately 1kg sub-samples were weighed, dried, crushed and pulverised to 85% passing 75 microns. The Competent Person considers the sample sizes appropriate to the grain size of the material sampled. No systematic collection of field duplicates or second-half core sampling has been recorded in the historical dataset. Gold at Hill End is coarse and nuggety, which is a recognised sampling and estimation challenge. It is addressed through the use of whole-sample screen fire assay, accelerated cyanide leach only for sample recovery and, more recently, photon assay methods, and through the application of a top-cut at the estimation stage. Samples are transported from site by Company personnel or a nominated contractor and delivered directly to the laboratory; underground face samples are collected into pre-numbered calico bags, secured and bagged under a Vertex submission code at the site office and couriered to the laboratory. The chain of custody is considered secure. Drilling techniques The database comprises approximately 4,230 drill holes and face samples. Surface diamond holes were drilled at NQ3 or HQ3 diameter and underground diamond holes at LTK48, with core oriented using the Ballmark method. Reverse circulation drilling used face-sampling bits, generally 130mm, with diamond core tails through mineralised zones. Diamond core recovery averaged greater than 99% with an average RQD of 75%, and no relationship between sample recovery and grade has been identified. Surface collars were surveyed by differential GPS and underground collars by total station, with downhole surveys by gyroscope or single-shot camera at 30m and thereafter at 50m intervals; detailed underground LiDAR scanning and surveyor pick-ups have been used to verify development, collar and face-sample positions. Drilling is oriented to intersect the steeply dipping lodes as close to perpendicular as practicable. No new drilling has been completed since the June 2023 estimate. The 2026 estimate is a re-interpretation and re-estimation of the existing drilling database, supplemented by the substantial body of new underground mapping, development exposure, face sampling and mine reconciliation data acquired between 2024 and 2026. Criteria used for classification, including drill and data spacing and distribution The Mineral Resource estimate has been classified as Indicated and Inferred. No Measured Mineral Resource estimate has been reported. Classification was determined by the Competent Person having regard to drill hole and sample spacing and distribution, the reliability of the sampling and assaying, the quality and representativeness of the assay and density data, the confidence in the geological interpretation and the continuity of the lodes, underground mapping and development exposure, and mine reconciliation data. The proportion of contained ounces classified as Indicated has increased from 31% in June 2023 to 37% in this estimate. Across the deposit, drill hole intercept spacing averages approximately 10m to 40m along strike and approximately 10m to 20m down dip, with underground drill fans providing intercepts as close as approximately 2m down dip. Downhole sample intervals range from 0.10m to 5.25m and average approximately 0.5m. Underground face sampling provides an effective sample spacing of approximately 3.5m along development. Indicated Mineral Resource estimates have been classified in those areas where drill hole intercept spacing is at the closer end of that range, generally of the order of 10m to 20m along strike and 10m to 20m down dip, and where that drilling is further supported by underground development exposure, underground mapping and face sampling at approximately 3.5m spacing, and by reconciliation of mined and processed material against the model. In these areas geological and grade continuity can be demonstrated with reasonable confidence. Inferred Mineral Resource estimates have been classified in those areas where drill hole intercept spacing is wider, generally of the order of 20m to 40m along strike, where there is no underground development exposure or face sampling control, and where confidence in short-range grade estimation is correspondingly lower. Sample analysis method Assay methods have varied over the life of the dataset and all are considered total methods appropriate to coarse gold. Samples predating January 2007 were analysed by screen fire assay at ALS Chemex in Orange, NSW. From January 2007, samples were analysed by SGS using accelerated cyanide leach only for sample recovery (Leachwell, method LWL69M) with a fire assay finish; bottle tails above 10 g/t Au were fire assayed and those above 50 g/t Au were screen fire assayed in order to capture coarse gold. Since 2025, substantially all Vertex samples have been submitted to SGS Orange for photon assay, a method well suited to coarse, nuggety gold. For the first several months of that programme one sample in ten was also 8 submitted to ALS Orange for comparative fire assay, and the comparison confirms acceptable accuracy and precision for the photon assay dataset going forward. For the historical dataset, accuracy and precision are considered established: 1,117 laboratory duplicate pairs returned a correlation coefficient of 99%; hard analysis shows 76% of pairs within plus or minus 15% for samples above 0.1 g/t Au against a target of 70%; quartz flush checks contributed a negligible 0.002 g/t Au; and certified reference material control charts fell within laboratory tolerance. The database has been validated for overlapping intervals, hole depth compatibility and collar elevations against surface survey, and closely spaced and twinned diamond hole pairs have been compared to confirm short- range grade continuity. No adjustment has been made to any assay other than the top-cut described below. Investors should note that within the model bounds, located quality control samples are restricted to historical drill holes at an insertion rate of approximately one in thirteen for standards and less than one in one hundred for field duplicates, that no located quality control samples exist for underground face samples, and that the Vertex quality assurance and quality control programme for current submissions is still being developed. Random duplicates are re-submitted to test laboratory instrument drift and repeatability. Estimation methodology The estimate was prepared by HGS Australia using Surpac software for data validation, geological and block modelling and grade estimation. Sample intervals were flagged from the interpreted wireframe solids and composited by domain using the straight downhole method. Grade was interpolated by ordinary kriging of both cut and uncut composite grades, with inverse distance squared estimation run as a validation check. Search parameters were established through a block optimisation process and applied over four passes: pass one using 6 to 12 samples within 20m; pass two using 4 to 12 samples within 40m; pass three using 2 to 12 samples within 80m; and pass four using 1 to 12 samples within 160m on an isotropic search. Gold is the only element estimated; there are no by-products and no deleterious elements requiring assumption. High grade cutting was determined using probability and histogram plots, and a top-cut of 200 g/t Au has been applied. A small number of extreme outlier assays exceed that value and their influence is material: reported on an uncut basis the estimate would be 276,000 tonnes at 21.57 g/t Au for 192,000 ounces, compared with 274,000 tonnes at 16.68 g/t Au for 146,900 ounces on the top-cut basis reported. The Company has elected to report the more conservative top-cut estimate, and both are disclosed in this announcement so that the effect of top-cutting is apparent to investors. Tonnages are estimated on a dry basis. Bulk density of 2.7 t/m³ has been applied, derived from specific gravity determinations on 101 samples of drill core. Dilution has been addressed by estimating to a minimum mining width of 1m, with waste grades assigned to the waste component of the block outside the modelled vein. No external audit or review of the Mineral Resource estimate has been undertaken; site resource geologists have been closely involved in the estimation process. The estimate is a global estimate. Confidence is materially improved relative to June 2023 as a result of underground exposure of the mineralised structures and reconciliation of mined and processed material against the resource model. The principal remaining sources of uncertainty are short-range grade variability arising from the coarse, nuggety nature of the gold, and the pending re-interpretation of lode geometry incorporating recent face sampling. Cut-off grade and the basis for the selected cut-off grade The Mineral Resource estimate is reported at a lower cut-off grade of 4.0 g/t Au. That cut-off is unchanged from the cut-off applied to the June 2023 estimate, so the two estimates are directly comparable, and the whole of the change between them is attributable to top-cutting and re-interpretation rather than to any change in reporting parameters. The 4.0 g/t Au cut-off has been selected by the Competent Person having regard to the narrow-vein selective underground mining methods in use at Reward, including a minimum mining width of approximately 1.4m and the dilution that entails; the simple, low-cost gravity processing route available on site; and the requirement of the JORC Code that reported Mineral Resources have reasonable prospects for eventual economic extraction. Mining and metallurgical methods and parameters, and