Mount Ridley Mines (ASX: MRD) has delivered its first gallium Mineral Resource Estimate at the Mt Ridley Project in Western Australia, defining one of the largest known clay-hosted gallium systems outside China. The resource totals 838.7 million tonnes at 29.3 ppm gallium using a 25 ppm cut-off, and complements the project’s existing rare earth inventory.
Large, Shallow and Regionally Extensive System
The resource spans three blocks over a 25-kilometre strike, with mineralisation starting from as little as four metres below surface. Drilling density across the project includes 732 holes for 30,112 metres, enabling Mount Ridley to convert historic nickel-copper drilling data into a multi-element critical-minerals dataset.
Block 1 hosts 164.1Mt at 29.8 ppm Ga, Block 2 contains 372.2Mt at 30.3 ppm Ga, while Block 3 holds 302.5Mt at 27.8 ppm Ga. All three zones display persistent gallium enrichment within saprolitic and lateritic clays. More than 70 per cent of the company’s 575 km² tenure remains untested.
Link Between Gallium and Heavy Rare Earths
Both Block 1 and Block 2 show a strong relationship between gallium and heavy rare-earth elements. Re-assay programs over historical pulps have confirmed elevated TREO grades, including up to 3,949 ppm TREO at Keith’s Prospect and 2,005 ppm TREO at Winston’s Prospect. These areas will anchor upcoming resource-definition work targeting heavy rare earths and scandium.
Development Pathway
Mount Ridley has begun designing metallurgical studies to evaluate combined gallium and rare-earth recovery. Testwork will assess clay-hosted leaching pathways and downstream hydrometallurgical options such as solvent extraction and ion exchange.
The company is also reviewing data for scandium, hafnium and germanium potential. Planning is underway for geophysical and drilling programs to close the 3-kilometre gap between Blocks 1 and 2 and test large untested zones to the east and west of Block 2.
Positioning Within a Shifting Global Market
China currently supplies more than 98 per cent of global gallium. Its 2024 export ban caused sharp price escalation and triggered downstream supply-chain concerns across semiconductor and defence industries. This context has elevated interest in new Western-aligned sources.
Mount Ridley’s shallow, clay-hosted system sits close to road and port access near Esperance, reinforcing its relevance to emerging U.S.–Australia strategic-minerals cooperation.
Mount Ridley Mines director Pedro Kastellorizos said: “The Mt Ridley Project represents one of the few new gallium discoveries outside of China, and it sits within an established rare-earth system.”
