Announcement PDF ASX RELEASE 3 APRIL 2025 MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL HIGHLIGHTS • Completion of a first Mineral Resource Estimate for the shallow disseminated nickel sulphide mineralisation at the Mulga Tank Ni-Co-Cu-PGE Project (reported in accordance with JORC 2012) • A major milestone in the life and progress of the Company’s flagship project • Globally significant, large-scale, open-pitable nickel sulphide deposit defined at 0.20% Ni cut-off: Indicated 565Mt at 0.28% Ni, 134ppm Co, 104ppm Cu, 18ppb Pt+Pd with S:Ni 1.0 Inferred 1,403Mt at 0.27% Ni, 129ppm Co, 73ppm Cu, 17ppb Pt+Pd with S:Ni 0.9 Total Resource 1,968Mt at 0.27% Ni, 131ppm Co, 82ppm Cu, 17ppb Pt+Pd with S:Ni 0.9 • Total Resource contained metal of 5.3Mt Ni, 257Kt Co, 161Kt Cu, 1.1Moz Pt+Pd • Mineral Resource constrained to depth and area of the Company’s current drilling results - with mineralisation open in many directions • Company’s modelling and Mineral Resource Estimate reviewed by independent consultants ERM Australia Consultants Pty Ltd (ERM) Western Mines Group Ltd (WMG or Company) (ASX:WMG) is very pleased to update shareholders on the completion of a first Mineral Resource Estimate for the shallow disseminated nickel sulphide mineralisation at the Mulga Tank Ni-Cu-Co-PGE Project, on the Minigwal Greenstone Belt, in Western Australia’s Eastern Goldfields a significant milestone for the project and the Company. Modelling of all the Company’s drilling results to date has identified a significant mineralised zone in the main body of the Mulga Tank Complex, which has been reported as a Mineral Resource, in accordance with JORC 2012. The Company’s internal modelling work has been reviewed by independent consultants ERM. The Mineral Resource Estimate using a 0.20% Ni cut-off grade is: Total Resource 1,968 million tonnes grading 0.27% Ni, 131ppm Co, 82ppm Cu, 17ppb Pt+Pd S:Ni 0.9 Of which: Indicated 565 million tonnes grading 0.28% Ni, 134ppm Co, 104ppm Cu, 18ppb Pt+Pd S:Ni 1.0 Inferred 1,403 million tonnes grading 0.27% Ni, 129ppm Co, 73ppm Cu, 17ppb Pt+Pd S:Ni 0.9 With contained metal within the Total Resource of: 5.3Mt Ni, 257Kt Co, 161Kt Cu and 1.1Moz Pt + Pd Western Mines Group Ltd Level 3, 33 Ord Street West Perth WA 6005 ASX:WMG Telephone: +61 475 116 798 Email: contact@westernmines.com.au www.westernmines.com.au Shares on Issue: 90.35m Share Price: $0.115 Market Cap: $10.39m Cash: $1.08m (31/12/24) 1 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL Commenting on the Mulga Tank Mineral Resource, WMG Managing Director Dr Caedmon Marriott said: “This is a very significant milestone for both the project and the Company and my thanks and congratulations go to the entire exploration team for the progress achieved over the last three years. Our exploration results from Mulga Tank have been continuously building as we unlock knowledge of the Complex and this Mineral Resource marks a culmination of that. It demonstrates what we have long stated - that the main body of the Complex hosts a globally significant nickel sulphide deposit, we believe the largest nickel sulphide deposit in Australia and top 10 in the world. The Mineral Resource Estimate focuses on just the shallow disseminated mineralisation, constrained by our current drilling, in what could be a large open pit scenario. We’ve got more than enough tonnes, and it will get bigger still as we extend in a number of directions. We will continue to infill and upgrade the resource confidence with further drilling but really the key now is to focus our exploration on the higher grade areas within this huge open-pitable volume - looking to followup on the 23 intersections greater than 1% nickel, including results up to 4.5% Ni and 4.8% Cu, clustering in various zones across the Complex.” MULGA TANK MINERAL RESOURCE ESTIMATE Exploration results from the Company’s various drilling programs at the Mulga Tank Project over the last two years have demonstrated significant nickel sulphide mineralisation and an extensive nickel sulphide mineral system within the Mulga Tank Ultramafic Complex (ASX, MTD023 Assays Confirm Discovery of Significant Nickel Sulphide System, 5 April 2023; MTD026 Assays - 840m of Nickel Sulphide Mineralisation, 30 August 2023; Over 1,200m of Sulphide Mineralisation in MTD029 (EIS), 19 February 2025). WMG has undertaken a combination of both diamond and reverse circulation (RC) drilling. With this two pronged approach, RC is used to infill and prove up the extent of shallow disseminated nickel sulphide mineralisation, defined by the Company’s JORC Exploration Target modelling (ASX, Mulga Tank JORC Exploration Target, 5 February 2024), whilst the diamond drilling program continues to test deeper targets for basal massive sulphide. Since the initial Exploration Target estimate, the Company has completed two further phases of RC drilling totalling 36 holes for 11,536m. Results from all the drilling to date have recently been incorporated into a block model that identifies a significant mineralised zone in the main body of the Mulga Tank Complex. This mineralised zone has been reported as a Mineral Resource Estimate, in accordance with JORC 2012. The Mulga Tank March 2025 Mineral Resource (Tables 1 and 2) at a 0.20% Ni cut-off grade is estimated to be: Indicated 565 million tonnes grading 0.28% Ni, 134ppm Co, 104ppm Cu, 18ppb Pt+Pd S:Ni 1.0 Inferred 1,403 million tonnes grading 0.27% Ni, 129ppm Co, 73ppm Cu, 17ppb Pt+Pd S:Ni 0.9 Total Resource 1,968 million tonnes grading 0.27% Ni, 131ppm Co, 82ppm Cu, 17ppb Pt+Pd S:Ni 0.9 Representing contained metal values of: Indicated Contained 1.6Mt Ni, 76Kt Co, 59Kt Cu and 327Koz Pt +Pd Inferred Contained 3.8Mt Ni, 181Kt Co, 102Kt Cu and 748Koz Pt +Pd Total Contained 5.3Mt Ni, 257Kt Co, 161Kt Cu and 1,075Koz Pt + Pd ASX:WMG www.westernmines.com.au 2 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL Ni Cut Off (%) 0.16 0.20 0.24 0.28 0.32 Category Tonnes (Mt) Ni (%) Co (ppm) Cu (ppm) Pt+Pd (ppb) S (%) S:Ni Indicated 573 0.28 134 105 18 0.29 1.0 Inferred 1,432 0.27 129 73 17 0.24 0.9 Total 2,005 0.27 131 82 17 0.25 0.9 Indicated 565 0.28 134 104 18 0.29 1.0 Inferred 1,403 0.27 129 73 17 0.24 0.9 Total 1,968 0.27 131 82 17 0.25 0.9 Indicated 501 0.28 134 104 18 0.28 1.0 Inferred 1,190 0.28 130 72 17 0.23 0.8 Total 1,692 0.28 131 82 16 0.24 0.9 Indicated 249 0.30 139 120 19 0.29 0.9 Inferred 443 0.30 134 83 17 0.25 0.8 Total 691 0.30 136 96 18 0.26 0.9 Indicated 44 0.34 158 229 28 0.40 1.2 Inferred 60 0.33 146 112 22 0.34 1.0 Total 103 0.33 151 161 25 0.37 1.1 Table 1: Mineral Resource details - tonnes and grades Numbers may not add up due to rounding Ni Cut Off (%) 0.16 0.20 0.24 0.28 0.32 Category Contained Ni (Mt) Contained Co (kt) Contained Cu (kt) Contained Pt+Pd (koz) Indicated 1.6 77 60 332 Indicated 3.8 185 105 766 Total 5.4 262 165 1,098 Indicated 1.6 76 59 327 Inferred 3.8 181 102 748 Total 5.3 257 161 1,075 Indicated 1.4 67 52 284 Inferred 3.3 154 86 614 Total 4.7 221 138 898 Indicated 0.8 35 30 151 Inferred 1.3 59 37 244 Total 2.1 94 66 395 Indicated 0.1 7 10 40 Inferred 0.2 9 7 42 Total 0.3 16 17 82 Table 2: Mineral Resource details - contained metals Numbers may not add up due to rounding ASX:WMG www.westernmines.com.au 3 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL WMG believes the Mulga Tank March 2025 Mineral Resource represents the largest nickel sulphide deposit in Australia and is likely in the top 10 nickel sulphide resources in the world. Figure 1 below shows the largest nickel sulphide deposits in Australia in terms of total resources of contained nickel metal (see Appendix 2): Contained Nickel (Kt) 6,000 4,500 3,000 1,500 0 1: Largest nickel sulphide resources in Australia by contained nickel metal (min. 100Kt Ni) BLOCK MODELLING DETAILS The Company focused its modelling work on an approximate 3.1km x 1.8km area in the centre of the main body of the Mulga Tank Complex. The relevant WMG drill holes from the project database used in the modelling are shown in Figure 2 below (Appendix 1). Figure 2: Plan view of area of investigation and drill holes used in block modelling ASX:WMG www.westernmines.com.au 4 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL The block model was divided into three geological domains, the sand cover, a narrow oxidised zone and then dunite containing disseminated sulphide mineralisation (Figure 7). The Mineral Resource Estimate is reported for the dunite domain only and nickel within the oxidised domain is specifically excluded from the reported results. The block model (Figure 3) used a parent block size of 50m x 50m x 10m (being approximately half the minimum drill spacing). Drill hole assay compositing was done at 2m with a top-cut of the 99th percentile nickel assay value of 6,958ppm Ni applied to the raw sample data. Inverse Distance Weighting (IDW2) estimation was performed using multiple passes at 250m, 400m and 800m search radius incorporating a minimum three drill holes. The first pass distance was determined from variography results for nickel (250m) and sulphur (300m). Two zones with closer drill hole spacing within the parent block model were identified and wireframed to define the resource classification boundaries. The first zone, with drill holes nominally spaced at 200m x 200m (and approximately corresponding to a first pass of 280m with minimum three drill holes), was defined as the Total Resource and classified as Inferred (Figure 4). Within this Total Resource, a second zone with drill holes nominally spaced at 100m x 100m (approximately corresponding to a first pass of 140m with minimum three drill holes) was classified as Indicated. Blocks within the mineralisation domain, but outside of the Indicated and Inferred classification boundaries, were categorised as Unclassified (Figure 5). >0.43% Ni 0.27% Ni <0.12% Ni Figure 3: Mulga Tank Parent Block Model for the dunite domain Outline of main Mulga Tank dunite body, viewed from south looking north, coloured by Ni% ASX:WMG www.westernmines.com.au 5 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL >0.43% Ni 0.27% Ni <0.12% Ni Figure 4: Mulga Tank Total Mineral Resource Block Model for the dunite domain Outline of main Mulga Tank dunite body, viewed from south looking north, coloured by Ni% Indicated Inferred Unclassified Figure 5: Mulga Tank Mineral Resource categories for the dunite domain Outline of main Mulga Tank dunite body, viewed from south looking north ASX:WMG www.westernmines.com.au 6 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL SUMMARY OF RELEVANT EXPLORATION DATA Since listing in July 2021 WMG has undertaken a series of exploration programs at the Mulga Tank Project which have included: 18 diamond drill holes totalling 13,446.2m 63 reverse circulation (RC) drill holes totalling 19,982.5m 20,330 drill hole assay samples 24,029 diamond core pXRF measurements Mineralisation and host rock characterisation including optical petrography, SEM-EDS microanalysis and whole rock quantitative XRD analysis Various geophysical surveys including: DownHole ElectroMagnetics (DHEM), Moving Loop ElectroMagnetics (MLEM), ground gravity and airborne MobileMT (MagnetoTellurics) In addition, historical exploration at the Mulga Tank project has included 12 diamond drill holes totalling 4,399.4m. These drill holes have been included in the project database when looking at the geological interpretation of the Complex and dimensions of the dunite intrusion but generally excluded from the geochemical modelling of mineralisation as the various historical assay suites often lacked elements WMG considers critical to the interpretation, such as sulphur (S), and/or the historical drill holes fell outside the area investigated by the modelling. INDEPENDENT REVIEW OF MINERAL RESOURCE ESTIMATE ERM has reviewed the data inputs and methodology used to generate the Mulga Tank Mineral Resource Estimate, including validation of the figures pertaining to this announcement. ERM is of the opinion that the input data is sound, and the interpretation and methodology used to generate the Mineral Resource Estimate is reasonable and acceptable by industry standards, for the type and style of mineralisation. ERM are satisfied the data, interpretation and methodology support the reporting of a Mineral Resource Estimate in accordance with the JORC Code (2012). ASX:WMG www.westernmines.com.au 7 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL TECHNICAL OVERVIEW The Company provides the following summary of material information relating to the Mineral Resource Estimate in accordance with ASX Listing Rule 5.8.1. Further details are provided in the accompanying JORC Tables. GEOLOGY AND GEOLOGICAL INTERPRETATION The Mulga Tank Project is located on the Minigwal Greenstone Belt, which lies in the southern Duketon Domain of the Burtville Terrane of the Yilgarn Craton, Western Australia (Figure 6). The Minigwal Greenstone belt is interpreted from aeromagnetics and historical drilling to consist of two belts of northwesterly trending assemblages of ultramafic, mafic volcanic and sedimentary rocks fault bounded by granite to the east and west. Figure 6: Location of Mulga Tank Project The eastern belt comprises faulted granite and gneiss with thrust-repeated interlayered units of greenstone, BIF and ultramafic to mafic volcanic rocks. The western belt comprises structurally controlled, steeply dipping ultramafic and mafic rocks adjacent to granites. Sub-parallel structures and dolerite dykes that trend east-west cut both belts. Within the project area the Archaean bedrock is masked by sand cover of up to 70m. The tenements cover the Mulga Tank Ultramafic Complex, interpreted from a major regional magnetic high and historical drilling. An approximately oval magnetic high feature within tenement E39/2132 has been shown by drilling to be a lopolith shaped dunite intrusion. The high MgO dunite consists of coarse-grained olivine, displaying predominantly adcumulate to extreme adcumulate texture, with varying degrees of serpentinisation, interstitial magnetite, minor chlorite and sulphides. In places complete serpentinisation of the dunite has taken place with former olivine cumulate textures pseudomorphically replaced by lizardite. Elsewhere serpentinisation has destroyed primary textural features. Curvilinear magnetic features emanating from the dunite are interpreted to represent komatiite channel flows. This interpretation of komatiite channels has been confirmed by the first recent regional RC drilling. The surrounding footwall of the dunite and komatiite channels consists of basalt and interbedded chert and sulphidic black shales. ASX:WMG www.westernmines.com.au 8 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL Diamond drilling of the dunite intrusion has demonstrated the extensive presence of intercumulus sulphide blebs (predominantly pentlandite), localised at the interstices between former olivine crystals. This texture is often considered evidence of cotectic olivine-sulphide precipitation and characteristic of Type 2 nickel sulphide systems, exemplified by the Mount Keith deposit. Drilling has also encountered intersections of thin (<20cm) high-tenor massive sulphide veins and immiscible sulphide globules. The presence of this type of mineralisation in addition to intercumulus sulphide is considered evidence that Mulga Tank represents a so-called Hybrid system, in which both cotectic precipitation and gravity settling of sulphides has occurred. This markedly increases the prospectivity of the system, allowing for possible significant basal accumulations of massive and matrix sulphide. DRILLING TECHNIQUES A combination of both diamond core and reverse circulation (RC) drilling has been undertaken by WMG at the Mulga Tank Project. Diamond core drilling was predominantly NQ2 diameter, with a minor amount of larger HQ core. Due to the sometimes free flowing sand cover mud rotary drilling was used to drill through the sand until competent rock, with the diamond or RC then commencing below the sand. A total of 18 diamond drill holes totalling 13,446.2m and 63 RC drill holes totalling 19,982.5m have been drilled across the project area since April 2022, of which, 11 diamond drill holes totalling 10,713.3m and 58 RC drill holes totalling 18,571.5m were drilled within the main body of the Mulga Tank Complex and used in the Mineral Resource Estimate. SAMPLING AND SUB-SAMPLING TECHNIQUES Diamond core was cut in half and quarters and sampled on either geological intervals or 1m or 2m lengths for geochemical analysis - the majority of sampling being 2m quarter core samples. Individual 1m RC samples were collected directly from the rig sampling system. SAMPLING ANALYSIS AND METHODS Samples were crushed and pulverised to >85% passing 75um to produce a sub-sample for analysis by four acid digest and multi-element ICP-AES (ME-ICP61), precious metals fire assay (Au, Pd, Pt) (PGM-ICP23) and loss on ignition at 1,000°C (ME-GRA05). Bulk density measurements on diamond drill core samples were performed by the water displacement method by the laboratory (OA-GRA09) and the Company. RESOURCE ESTIMATION METHODOLOGY The Mulga Tank March 2025 Mineral Resource Estimate is based on the WMG Mulga Tank drilling database which includes all drilling results up until end of February 2025. Standard database validation checks and analysis, including analysis of QAQC data, was completed prior to the resource estimation work. The area of interest was wireframed and divided into three geological domains (Figure 7): SAN - the sand cover above the Mulga Tank Complex (density 1.5) - all drill hole collars located by DGPS and used to create Sand Cover Surface DTM OX - a narrow oxidised zone between the sand cover and dunite (density 2.3) UD - dunite containing disseminated sulphide mineralisation (density 2.7) - which was limited to a floor depth of 50RL, approximately 400m below surface. This is ~80m deeper than the average RC drill hole depth of ~320m, with 32 of the 58 RC end in mineralisation and continuing mineralisation demonstrated in deeper diamond holes ASX:WMG www.westernmines.com.au 9 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL SAN OX UD Figure 7: Mulga Tank wireframe geological domains Outline of main Mulga Tank dunite body, viewed from south looking north Drill hole sample assay data was composited to 2m downhole lengths based on statistical analysis of sample data (2m, 3m and 5m comparison) and sample length distributions (81% 1m, 17% 2m, 2% <1m). Given the focus of the resource on predominantly Type 2 disseminated nickel sulphide mineralisation a top-cut of the 99th percentile nickel assay value of 6,958ppm Ni was applied to the raw sample data. Hard domain boundaries were used between the geological domains, meaning only composites within the domain were used to estimate inside that domain. Variography was undertaken on the composited sample data, with particular focus on nickel and sulphur, and used to determine search parameters and the first past search distance. The variogram models for Ni suggest a search of 300m in both the X and Y directions and about 20-30m in the Z direction and for S suggest about 250m in the X and Y directions and about 30m in the Z direction (Figure 8). A first pass search radius of 250m in the X and Y direction and 30m in the Z direction were chosen for Inverse Distance Weighting (IDW2) estimation. Figure 8: Variogram models for Ni (left) and S (right) ASX:WMG www.westernmines.com.au 10 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL Each of the geological domains were block modelled using a parent block size of 50m x 50m x 10m, being approximately half the minimum drill spacing, creating a block model with dimensions 3,100m x 1,600m x 410m. The Inverse Distance Weighting (IDW2) estimation method was used to estimate Ni, S, Co, Cu, Pd, Pt and Cr into the 3D block model with estimation performed in three passes: First Pass - 250m search radius incorporating a minimum three drill holes Second Pass - 400m search radius incorporating a minimum three drill holes Third Pass - 800m search radius incorporating a minimum three drill holes Whilst all three domains were block modelled the Mineral Resource Estimate is reported for the dunite domain (UD) only and nickel within the oxidised domain (OX) is specifically excluded from the reported results. Validation of the block model was completed by: • Visual inspection of the block model estimation in comparison to raw and composited drill data on a section-by-section basis (Figure 9) • Volumetric comparison of the wireframe/solid volume to that of the block model volume for each domain • Global statistical comparison of input and block grades, and local composite grade relationship plots (swath plots, to the block model estimated grade for each domain Figure 9: Visual inspection of block model and drill hole composites (section NS along E520876) CLASSIFICATION CRITERIA Two zones with closer drill hole spacing within the parent block model were identified and wireframed to define the resource classification boundaries. The first zone, with drill holes nominally spaced at 200m x 200m (and approximately corresponding to a first pass radius of 280m with minimum three drill holes), was defined as the Total Resource and classified as Inferred. Within this Total Resource, a second zone with drill holes nominally spaced at 100m x 100m (approximately corresponding to a first pass radius of 140m with minimum three drill holes) was classified as Indicated. Blocks within the mineralisation domain, but outside of the Indicated and Inferred classification boundaries, were categorised as Unclassified (Figure 5). ASX:WMG www.westernmines.com.au 11 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL CUT-OFF GRADES The Mulga Tank March 2025 Mineral Resource Estimated is reported at cut-off grade of 0.20% Ni. This cut-off grade was chosen for a number of reasons: • Preliminary metallurgical test work suggests approximately ~0.10% Ni in silicate within the test bulk sample so a cut-off of twice this value was deemed appropriate • Many Canadian large, low-grade nickel sulphide deposits such as Canada Nickel Company’s Crawford Project use a cut-off grade of 0.10% Ni (Crawford Nickel Sulphide Project NI 43-101 Technical Report and Feasibility Study, 1 October 2023) so a cut-off of twice this value, and close to the Crawford Project overall average grade of 0.23% Ni, was deemed appropriate to emphasise the potential superiority of the Mulga Tank deposit • A cut-off of 0.20% Ni was calculated using the cut-off grade calculation formula: Economic Cut-Off = (M + P + O) / r x (p-v) Where M = mining cost, P = processing cost, O = overhead/G&A cost, r = metallurgical recovery, p = nickel price and v = selling cost MINING AND METALLURGICAL TEST WORK AND PARAMETERS Given the shallow nature of the mineralisation, modelled to a limit of 50mRL or approximately 400m below surface, it is anticipated that material would be extracted by open pit mining and then processed on-site by conventional flotation mineral beneficiation methods to produce a saleable nickel sulphide concentrate. The large low-grade resource would be best exploited by a large scale operation, benefiting from the economies of scale. Peer comparison against similar large low-grade gold and base metal projects suggest a modern large open pit operation with a mining and processing rate of 30Mt to 40Mt per year of ore could be envisaged. The key variables in exploiting a deposit on this scale would be unit mining cost, strip ratio, unit processing cost and metallurgical recovery. WMG has conducted preliminary benchmarking studies on a number of global large low-grade nickel sulphide deposits, as well as, benchmarking against large-scale gold and base metal project in Western Australia, in order to gauge potential unit operating costs and project parameters (Table 3). Comparison of these results suggests likely unit operating costs within the range: mining US$ 3-4/t, processing US$5-7/t. Assuming an additional G&A cost of US$ 1/t then an onsite total processing cost of US$10/t is assumed for the assumption of Reasonable Prospects of Economic Extraction in the section below. Based on analysis of the block model results for the tonnes within the overburden sand (SAN) and oxidised (OX) domains a life-of-mine (LoM) strip ratio of 1:1 is assumed for the Mulga Tank deposit. WMG is undertaking preliminary metallurgical test work on a bulk sample of material taken from the upper portion (150m to 300m) of diamond hole MTD029 (EIS3). A series of different rougher flotation tests have been conducted on the bulk sample material, each testing a range of different factors including grind size (38um to 150um) and various reagents. Nickel sulphides have been successfully recovered in all of the tests, with the test work suggesting around ~0.1% Ni is present as non-sulphide silicate nickel - implying a maximum theoretical nickel recovery of ~63% based on the 0.27% average grade of the Mineral Resource Estimate. ASX:WMG www.westernmines.com.au 12 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL Project/Source Costmine Intelligence (Global mining cost database) Canada Nickel - Crawford Nickel Project (Crawford Nickel Sulphide Project NI 43-101 Technical Report and Feasibility Study, 1 October 2023) Dumont Nickel - Dumont Nickel Project (Technical Report on the Dumont Ni Project, Launay and Trécesson Townships, Quebec, Canada, 11 July 2019) Chalice Mining - Gonneville Project (Gonneville Nickel-Copper-PGE Project Scoping Study, 29 August 2023) Newmont - Boddington Gold Mine (Boddington Operations Western Australia, Australia, NI 43-101 Technical Report, 31 December 2018) Newmont - Boddington Gold Mine (Newmont Annual Report 2024) Operation Size Unit Mining Cost Unit Processing Cost 29.2Mtpa US$ 2.20 per tonne US$ 6.80 per tonne 43.8Mtpa US$ 4.78 per tonne ore US$ 5.19 per tonne ore 38.3Mtpa C$ 3.82 per tonne ore C$ 5.20 per tonne ore 30Mtpa A$ 3.80 per tonne mined A$ 27.50 per tonne processed 40.2Mtpa A$ 4.22 per tonne ore A$ 9.71 per tonne ore 34.9Mtpa US$ 17.58 per tonne direct mining and production cost with ~1:1 strip ratio for 2024 Caravel Minerals - Caravel Copper Project (Caravel Copper Project Pre-Feasibility Study, July 2022, and Caravel Copper Project Pre-Feasibility Study Update, 20 September 2022) 27Mtpa (Strip ratio 2.3:1) (Strip ratio 1:1) (Strip ratio 1.8:1) (Strip ratio 1:1) A$ 3.06 all-in per tonne mined (Strip ratio 1.3:1) (Hydrometallurgical processing) A$ 9.26 all-in per tonne ore Table 3: Benchmarking unit operating costs of various large low-grade nickel, gold and base metal projects The Company notes the recoveries used in feasibilities studies for Canadian large low-grade nickel sulphide projects such as Crawford and Dumont of 41% LoM and 43% LoM respectively. These fall within the range of results achieved by WMG to date and the Company will use the assumption of 40% recovery for Mulga Tank for the time being until more extensive test work has been completed. REASONABLE PROSPECTS FOR EVENTUAL ECONOMIC EXTRACTION WMG believes the Mulga Tank deposit has very reasonable prospects for eventual economic extraction, which is why the Company has continued to explore and advance the project even during the current downturn in the nickel price cycle. Whilst at an earlier stage, the Company notes the higher nickel grade, and other beneficial factors such as four times the S:Ni ratio, of the Mulga Tank deposit when compared to more advanced projects such as Canada Nickel’s Crawford Nickel Project that has completed a full feasibility study. The Company uses the BOTE methodology to continuously evaluate early stage projects and drive capital management decisions: Based on a current trough nickel price of ~US$16,000/t, the recoverable value per tonne of ore from the Mulga Tank deposit is US$17.30 per tonne assuming 40% recovery and 0.27% Ni grade ($16,000 x 0.27% x 40%). Based on peer comparison of large scale open pit mining operations an onsite total processing cost of US$10.00 per tonne is assumed for a 40Mtpa operation at Mulga Tank (Mining and Metallurgical Methods and Parameters above). This represents a profit margin of US$7.30 per tonne of ore at trough nickel prices. Assuming a desired minimum 12% Return on Invested Capital (ROIC) even at trough nickel prices then a capital intensity of US$45.63 per annual tonne of ore processed could be supported by the trough profit margin ($7.30/ t x 25% tax / $48.70/t = 12% ROIC). Based on the 40Mtpa operation this would represent potential project capex of up to US$1.83Bn ($45.63/t x 40Mt = $1.825Bn), which the Company believes is a realistic threshold when compared to peer projects. ASX:WMG www.westernmines.com.au 13 ASX RELEASE | MULGA TANK MINERAL RESOURCE OVER 5MT CONTAINED NICKEL From the broad calculations above, which the Company believes are suitable for the current early stage nature of the project, WMG is confident the Mulga Tank deposit has Reasonable Prospects for Eventual Economic Extraction. The Company is pleased to present this first Mineral Resource Estimate for the Mulga Tank Project. It represents a significant milestone for the project. The team is excited to continue to advance the project and is in the process of planning and developing further exploration programs