Metallic Minerals' 100%-owned La Plata Project in southwestern Colorado hosts a large, expanding copper-silver resource with significant platinum, palladium and gold potential. Supported by a strategic investment from Newmont, the project combines an established mineral resource with substantial exploration upside and emerging opportunities in innovative metallurgy and critical minerals research.
Following a strategic equity investment by Newmont Mining in August 2025,¹ Metallic Minerals announced an updated NI 43-101 Inferred Mineral Resource Estimate for the project within the central Allard Cu-Ag porphyry deposit (January 26, 2026).²
The Company acquired the project in 2019 and has defined an Inferred Mineral Resource of 181.4 million tonnes grading 0.36% CuEq (0.33% Cu and 2.9 g/t Ag), containing 1.307 billion pounds of copper and 17.0 million ounces of silver, or 1.455 billion pounds of copper equivalent. The updated resource includes a 45.4 Mt subset containing platinum, palladium and gold, totaling 272,000 ounces of 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 constrained within a block-cave optimized underground mining shape using an NSR cut-off of US$18/t.²
The Allard deposit remains open to significant expansion within the resource area and the greater La Plata Cu-Ag-Au-PGE project remains underexplored and open to new discoveries of both additional Cu porphyry centers as well as high-grade epithermal Ag and Au systems.
Significant Copper-Silver Resource: The 2026 Mineral Resource Estimate outlines 181.4 million tonnes of inferred resources grading 0.36% CuEq, containing approximately 1.31 billion pounds of copper and 17.0 million ounces of silver.
Precious Metals Upside: A 45.4 Mt subset of the resource also contains approximately 60,000 ounces of gold, 91,000 ounces of platinum and 121,000 ounces of palladium, highlighting the project's polymetallic potential.
Additional Critical Minerals Potential: Beyond copper, silver, gold and platinum group metals, the La Plata district offers exploration potential for additional high-priority U.S. critical minerals, including hafnium, zirconium, gallium, scandium, fluorspar, tellurium and rare earth elements, providing opportunities to further expand the project's strategic mineral profile.
Substantial Exploration Potential: The Allard deposit remains open for expansion along strike and at depth, with drilling confirming extensive copper-silver mineralization and associated precious metals.
District-Scale Opportunity: Sixteen additional potential porphyry centres have been identified across the broader La Plata property, alongside high-grade epithermal silver, gold and tellurium targets.
Advanced Exploration Targeting: Modern geophysics, geological mapping and geochemical sampling continue to refine priority targets and identify opportunities for resource expansion and new discoveries.
U.S. Department of Energy Collaboration: Metallic Minerals is participating in a U.S. Department of Energy-supported research initiative with the Colorado School of Mines through the Genesis Mission AGAPEX program, advancing innovative exploration technologies and critical minerals discovery.
Favourable U.S. Jurisdiction: Located in southwestern Colorado, La Plata offers exposure to copper, precious metals and potential additional critical minerals in an established U.S. mining district.
Project History
The La Plata mining district has a rich history dating back to the 1700s, with high-grade silver and gold production from more than 90 mines and prospects between the 1870s and early 1940s. From the 1950s through the 1970s, major mining companies, including Rio Tinto, Exxon and Freeport-McMoRan, explored the district for large-scale porphyry copper mineralization.
Historical exploration included 25,532 metres of drilling across 88 holes, confirming a large, multi-phase copper-silver-gold porphyry system associated with a 10 km² magnetic anomaly. Freeport-McMoRan retained claims in the district until 2002.
Metallic Minerals acquired the La Plata project in 2019, becoming the first company in nearly 50 years to undertake significant modern exploration. Since acquisition, the Company has advanced the Allard deposit through systematic drilling, geophysics, geological mapping and geochemical sampling.
Key Exploration Milestones:
2022: Completed 1,730 metres of drilling, including hole LAP22-04, which intersected 816.0 metres grading 0.41% recovered CuEq, demonstrating the scale and higher-grade potential of the Allard deposit.
2023: Completed 4,530 metres across four diamond drill holes, with all holes intersecting extensive porphyry-style mineralization. Hole LAP23-05 returned 909.0 metres grading 0.26% recovered CuEq from surface. District-wide exploration also identified numerous high-grade silver-gold targets.
2024: Advanced geological mapping, soil and rock sampling, refining priority exploration targets beyond Allard. The Company also expanded environmental, permitting and community engagement activities.
The Allard deposit remains open for expansion, with mineralization extending over a kilometre vertically. Beyond the resource area, Metallic Minerals has identified 16 additional potential porphyry centres, along with high-grade epithermal silver-gold targets, highlighting the district-scale exploration potential of La Plata.
The project also hosts platinum group metals and documented occurrences of tellurium and rare earth elements, providing additional opportunities for future exploration.
Explore the La Plata Project Virtual Tour: https://vrtuous.com/tools/loader/la-plata/
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