Key Highlights

  • The Grass Patch Project now hosts an Inferred Mineral Resource of 946Mt at 50.1 ppm scandium for 47,357 tonnes of contained scandium metal, reported at a 25 ppm cut-off.
  • The company describes this as the largest publicly reported JORC (2012) scandium resource globally, co-located with existing heavy rare earth and gallium resources.
  • Initial testwork of the wholly owned, patent-pending Selectro Process has returned scandium recoveries of 80%, with potential to recover scandium, heavy rare earth and gallium from a single leach circuit.
  • A Phase 2 re-assay program is underway across the Grass Patch Complex, with approximately 80% of Mount Ridley's tenure remaining untested.

Mount Ridley Mines Limited (ASX:MRD), trading at $0.036 and up 12.50% on the day, has reported an upgraded Scandium Mineral Resource Estimate at its Grass Patch Project, located 25 kilometres northeast of Esperance in Western Australia. The company says the upgrade positions Grass Patch as what it considers to be the largest publicly reported JORC (2012) scandium resource globally, co-located with previously defined heavy rare earth and gallium resources.

Upgraded Scandium Resource

The upgraded Inferred Mineral Resource stands at 946Mt at 50.1 ppm scandium (76.8 ppm Sc2O3), for 47,357 tonnes of contained scandium metal and 72,637 tonnes of contained Sc2O3, reported at a 25 ppm cut-off. The resource comprises two blocks defined along the same geological corridor within the Grass Patch Complex. Block 1 contains an Inferred Resource of 367.45Mt at 50.3 ppm scandium (77.3 ppm Sc2O3) for 18,475 tonnes of contained scandium, while Block 2 contains an Inferred Resource of 578.63Mt at 49.9 ppm scandium (76.5 ppm Sc2O3) for 28,882 tonnes of contained scandium.

The upgrade follows a Phase 1 scandium re-assay program across both blocks, in which 3,271 historical aircore and diamond drill pulp samples were re-assayed. The re-assay work returned near-surface scandium intersections that consistently exceeded the previous average resource grade, and the company noted that many drillholes terminated in mineralisation, indicating the system remains open at depth and laterally.

Selectro Process and Multi-Element Potential

Mount Ridley holds a wholly owned, patent-pending processing technology called the Selectro Process, designed to recover scandium, heavy rare earth elements and gallium simultaneously from a single leach circuit. Initial testwork under this process has returned scandium recoveries of 80%. The company says the spatial coincidence of scandium and gallium mineralisation within the same regolith profile provides a favourable technical setting for this approach, offering potential Capital and operating cost efficiencies compared with standalone single-commodity processing.

The company noted that scandium's strategic significance was underscored in August 2026 when the US Department of War committed a US$400 million conditional Loan to Sunrise Energy Metals Limited (ASX:SRL) for its Syerston scandium project, which it says highlights an emerging global scandium Supply shortage. Scandium is used in high-value applications including aerospace, defence and solid oxide fuel cells.

Next Steps

Mount Ridley is progressing additional density testwork required to support upgrading portions of the resource to higher confidence categories, and a Phase 2 re-assay program is underway across the Grass Patch Complex. The company says its resource growth strategy leverages re-assay of existing historical drill data as a capital-efficient pathway to further upgrades ahead of any new drilling spend, noting that approximately 80% of its tenure remains untested, with multiple geophysically defined target corridors still to be explored.

Conclusion

Mount Ridley's upgraded scandium resource at Grass Patch adds a globally significant scandium inventory to a project already hosting heavy rare earth and gallium mineralisation, with early Selectro Process testwork indicating a potential pathway to recover all three commodities from a single processing circuit. With a Phase 2 re-assay program underway and the majority of its tenure yet to be tested, the company's near-term focus will be on further resource definition and density testwork ahead of any future drilling decisions.