Resource Estimates

La Plata - Colorado, USA

Metallic Minerals is pleased to announce an updated NI 43-101 Mineral Resource Estimate (the “2026 MRE”) at the Allard deposit within its La Plata project in southwestern Colorado.

The 2026 MRE expands the Inferred Resource tonnage by 23% and adds platinum, palladium and gold, supported by an additional 4,530 metres of diamond drilling completed since the previous resource estimate reported in 2023.

The 2026 MRE now totals 181.4 million tonnes (“Mt”) at an average grade of 0.36% copper equivalent (“CuEq") (0.33% Cu and 2.9 grams per tonne (“g/t”) Ag containing 1,307 million pounds (“Mlbs”) of copper and 17.0 million ounces (“Moz”) of silver or 1,455.1 Mlbs CuEq, constrained within a block-cave-optimized underground mining shape. The updated resource includes a 45.4 Mt subset containing 91,000 oz of platinum, 121,000 oz of palladium, and 60,000 oz of gold totalling 272,000 ounces of platinum group elements plus gold (“PGE+Au”) grading 0.18 g/t PGE+Au (0.06 g/t Pt, 0.08 g/t Pd and 0.04 g/t Au).The resource is estimated using an NSR cut-off of US$18/t (See Notes to Table 1).

Highlights

• The 2026 MRE consists of two continuous, adjoining mineralized shells: (i) a copper-silver shell based largely on 1950 to 1970s-era drill holes; and (ii) a copper-silver-platinum-palladium-gold shell supported by Metallic’s multi-element drill core sampling.
• Metallic-era drill results of 8,240 m from the 2021 to 2023 drill and underground sampling programs support the estimation of a Cu-Ag-PGE+Au bearing subset that represents 25% of the total resource tonnage.
• The inclusion of co-occurring precious metals (Pt, Pd, and Au) results in a 17% higher copper-equivalent grade for the 45.4 Mt subset (0.41% CuEq vs 0.35% CuEq) relative to a copper-and-silver-only equivalent of the same subset.
• Significant upside exists for further increases in equivalent grade and precious metal content across the broader deposit with additional drilling, due to limited historic assaying for gold, platinum and palladium (see Figure 1).
• The Allard resource is one of only three PGE-bearing development-stage resources in the USA and remains open to expansion at depth and along strike.
• Sixteen (16) untested potential porphyry centers have been identified on the greater La Plata project area, as well as target areas with potential for significant high-grade epithermal silver, gold and telluride mineralization.

Table 1 – 2026 Updated La Plata Inferred Mineral Resource Estimate

Notes:

1. The Mineral Resource Estimate has been prepared according to CIM (2014) Standards and using CIM (2019) MRMR Best Practice Guidelines.
2. Mineral Resources are estimated using a long-term copper price of US$4.50/lb, silver price of US$32/oz, gold price of US$2,500/oz, platinum price of US$1,300/oz, and palladium price of US$1,200/oz. Metallurgical recoveries for copper, silver, gold, platinum, and palladium are 90%, 70%, 60%, 50% and 50%, respectively.
3. CuEq% is calculated based on the above metal prices and recoveries, resulting in CuEq = Cu% + (Ag g/t)*0.008 + (Au g/t)*0.540 + (Pt g/t)*0.234 + (Pd g/t)*0.216
4. Underground Mineral Resources are reported using an NSR cut-off of US$18/t. This assumes a block caving mining method with a mining cost of US$5/t, processing cost of US$6/t and G&A cost of US$7/t.
5. Underground Mineral Resources are reported within a block-caving shape generated by Deswik Stope Optimizer.
6. A constant SG value of 2.55 has been applied to all blocks in the model.
7. Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. Numbers may not add due to rounding.
8. An NI 43-101-compliant technical report on the 2026 La Plata Resource will be filed on sedarplus.ca within 45 days.
9. The QP responsible for this Mineral Resource estimate is Brian Hartman, M.S., P.Geo. of SLR USA Advisory Inc.

Figure 1 – La Plata Isometric Cross-Section showing Grade Shells and Resource Expansion Opportunities (looking SW)

Figure 1 shows the current geometry of the Allard deposit CuEq model, highlighting a vertically extensive, continuous mineralized system with a thick, higher-grade core within a broader mineralized envelope. Mineralization has been drill-defined from surface to greater than 1.5 km depth, over approximately 600 m of strike length and up to 400 m in width, supporting the potential suitability for a bulk underground, block cave mining approach. Importantly, multiple drill holes terminate in higher-grade mineralization within and below the modeled shells, indicating the system remains open along strike and at depth and highlighting significant potential for further resource expansion through step-out drilling.

The PGE+Au-bearing component of the 2026 MRE is currently constrained largely by limited historic assaying for platinum, palladium and gold outside Metallic’s multi-element sampling coverage, and represents a clear opportunity to expand the precious-metals footprint through additional drilling and systematic multi-element assaying.

NSR Cutoff Sensitivity Analysis

In addition to the base-case Inferred Mineral Resource reported at an NSR cut-off of US$18/t [average gross value per tonne of US$36/t], a sensitivity analysis showing the Inferred Mineral Resource across a range of NSR cut-off values is shown below in Table 2. This sensitivity analysis illustrates the relationship between cut-off, tonnage, grade and contained metal under a reasonable range of potential economic assumptions.

The US$18/t NSR cut-off is considered appropriate for reporting purposes and is based on conceptual underground bulk-mining (block cave) assumptions using metal prices of US$4.50/lb copper and US$32/oz silver, together with assumptions for metallurgical recoveries, payables and operating costs as described in the Notes to Table 1.

Overall, the sensitivity analysis highlights the potential flexibility of the Allard deposit, including the ability (in future technical studies) to evaluate scenarios that prioritize higher-grade material, increased precious-metal contributions, and/or staged mining approaches, subject to further technical and economic evaluation. As the NSR cut-off increases, tonnage decreases while copper-equivalent grade increases, reflecting the higher-grade core within the broader mineralized envelope. At higher cut-offs, the model also shows increasing precious metal grades (Pt, Pd and Ag), consistent with the higher-grade portions of the system.

Table 2 – Inferred Mineral Resource Sensitivity to NSR cut-off (US$/t)

Notes:

1. Sensitivity cases are presented for information purposes only and do not represent additional or separate mineral resources.
2. Mineral resources are not mineral reserves and do not have demonstrated economic viability.

Metallic Minerals announced an updated NI 43-101 Inferred Mineral Resource Estimate for the La Plata project in July 2023, representing a 25% increase in tonnage based on an additional 1,730 m of diamond drilling completed in 2022. Inferred Mineral Resources at the Allard deposit now total 1,211 Mlbs of Cu and 17.6 Moz of Ag in a constrained model with 147.3 Mt at an average grade of 0.41% CuEq (0.37% Cu and 3.72 g/t Ag) using a 0.25% CuEq cut-off grade¹.

The expansion from the inaugural Inferred Mineral Resource to the current 1,317 Mlbs CuEq (0.37% Cu and 3.72 g/t Ag)¹ is largely driven by the major discovery in drill hole LAP22-04 (drilled in 2022), which intersected 816.0 m of 0.41% CuEq (0.30% Cu, 2.47 g/t Ag, 0.04 g/t Au, 0.06 g/t Pt and 0.09 g/t Pd) ending the hole in 5.39% CuEq over 5.2 m (2.44% Cu, 18.7 g/t Ag, 0.47 g/t Au, 1.76 g/t Pt and 2.78 g/t Pd)².

The greater La Plata Cu-Ag-Au project remains underexplored and open to new discoveries of both additional porphyry Cu centers as well as high-grade epithermal Ag and Au systems.

La Plata Inferred Mineral Resource Estimate at a Base Case Cut-off Grade of 0.25% CuEq with Grade and Contained Metal Sensitivity Analysis at Various CuEq Cut-off Grades, July 12, 2023³

Keno Silver - Yukon, Canada

An inaugural NI 43-101 Inferred Mineral Resource Estimate was announced in February 2024 showing the Keno Silver project to host 18.2 Moz AgEq grading 223 g/t AgEq (120 g/t Ag, 0.10 g/t Au, 0.80% Pb and 1.77% Zn)⁴ in four shallow deposits, each of which remains completely open at depth and along strike (click here for full mineral resource estimate).

Underground Inferred Mineral Resources, restricted to the Formo deposit, are estimated at 1.08 Mt grading 206 g/t Ag, 0.08 g/t Au, 1.52% Pb, and 2.79% Zn (369 g/t AgEq)⁴. The Estimate includes 7.11 Moz of Ag, 3,000 Oz of Au, 36.02 Mlbs of Pb, and 66.14 Mlbs of Zn (12.8 Moz AgEq at a 150 g/t AgEq cut-off)⁴. Formo is the largest and highest-grade contributor to the 2024 Estimate.

In-Pit Inferred Mineral Resources are estimated at 1.46 Mt grading 58 g/t Ag, 0.12 g/t Au, 0.28 % Pb, and 1.02% Zn (115 g/t AgEq) and include resources of 2.70 Moz of Ag, 5,500 Oz of Au, 8.86 Mlbs of Pb, and 32.95 Mlbs of Zn (5.40 Moz AgEq at a 50 g/t AgEq cut-off).⁴

The resource is the culmination of 19,701 m of drilling from 168 drill holes over six active field seasons. Subsequent campaigns, anticipated to commence in the 2025 field season, will focus on resource expansion through the drilling of extensions to current deposits, definition drilling of very prospective early-stage drilled targets to new resources, as well as targeting new discoveries at high-priority targets that have yet to be drill tested.

Keno Project Inferred Mineral Resource Estimates at an In-Pit Base Case Cut-off Grade of 50 g/t AgEq and Underground Base Case Cut-off Grade of 150 g/t AgEq, February 1, 2024⁵

Footnotes:

1. See La Plata News Release dated January 26, 2026 and Technical Report dated January 23, 2026.
2. See La Plata News Releasedated July 31, 2023 and Technical Report dated September 14, 2023.
3. SeeLa Plata News Releasedated February 28, 2023.
4. The Allard deposit Inferred Mineral Resource Estimate:

1. Uses an effective date of July 12, 2023.
2. Were estimated by Allan Armitage, Ph.D., P.Geo of SGS Geological Services and is an independent Qualified Person as defined by NI 43-101.
3. Are classified using the CIM Definition Standards - For Mineral Resources and Mineral Reserves (2014). Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. It is reasonably expected that the majority of the Inferred Mineral Resource could be upgraded to an Indicated Mineral Resource with continued exploration.
4. All tonnage, grade and contained metal content estimates have been rounded; rounding may result in the apparent summation differences between tonnes, grade, and contained metal content.
5. May be mined using a large-scale underground bulk mining method.
6. Are reported at a base case cut-off grade of 0.25% CuEq, based on metal prices of $3.75/lb Cu and $22.50/oz Ag, assumed metal recoveries of 90% for Cu and 65% for Ag, a mining cost of US$5.30/t rock and processing and G&A cost of US$11.50/t mineralized material. CuEq % = Cu % + (Ag g/t x Ag price/gram).
7. Values in the Mineral Resource table reported above and below the base-case cut-off 0.25% CuEq are only presented to show the sensitivity of the block model estimate.
8. Composites of 3.05 m in length, constrained to the Allard domain, are used for the resource estimation procedure. Grades for Cu and Ag were interpolated into blocks by the Inverse Distance Squared (ID²) calculation method.
1. The estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues.

4. See Keno Silver News Release dated February 26, 2024 and Technical Reportdated April 11, 2024.
5. The Keno Project Inferred Mineral Resource Estimate:
   1. Uses an effective date of February 1, 2024.
   2. Were estimated by Allan Armitage, Ph.D., P.Geo of SGS Geological Services and is an independent Qualified Person as defined by NI 43-101.
   3. Are classified using the CIM Definition Standards - For Mineral Resources and Mineral Reserves (2014). Mineral Resources that are not Mineral Reserves do not have demonstrated economic viability. It is reasonably expected that the majority of the Inferred Mineral Resource could be upgraded to an Indicated Mineral Resource with continued exploration.
   4. All tonnage, grade and contained metal content estimates have been rounded; rounding may result in the apparent summation differences between tonnes, grade, and contained metal content.
   5. Caribou, Fox and Homestake deposits may be mined using open-pit mining methods and are reported at a base case cut-off grade of 50 g/t AgEq based on metal prices of $22.50/oz Ag, $1,800/oz Au, $1.00/lb Pb and $1.30/lb Zn, and considers metal recoveries of 95% for Ag, 50% for Au, 94% for Pb and 88% for Zn. AgEq = Ag ppm + (((Au ppm x Au price/gram) + (Pb% x Pb price/t) + (Zn% x Zn price/t))/Ag price/gram).The deposits consider a mining cost of US$2.20/t mined, and processing, treatment, refining, G&A and transportation cost of USD$25.00/t of mineralized material.
   6. The Formo deposit may be mined using underground mining methods and is reported at a base case cut-off grade of 150 g/t AgEq based on the same metal prices and metal recoveries. Formo is envisioned to be mined using a combination of underground mining methods including sub-level stoping (SLS) and/or cut and fill (CAF) mining with a mining cost of US$65.00/t mined, and processing, treatment, refining, G&A and transportation cost of USD$25.00/t of mineralized material.
   7. The estimate of Mineral Resources may be materially affected by environmental, permitting, legal, title, taxation, socio-political, marketing, or other relevant issues.