Mount Ridley Mines Limited has upgraded the inferred scandium resource at its Grass Patch Deposit in Western Australia to 946 million tonnes at 50.1 ppm scandium, more than doubling the contained metal inventory from its previous estimate.

The updated JORC 2012 resource encompasses 47,357 tonnes of contained scandium metal and 72,637 tonnes of scandium oxide, reported at a 25 ppm cut-off. The revised inventory compares against the company's maiden scandium resource reported in January 2026, which totaled 367.98 million tonnes at 57.3 ppm scandium for 18,855 tonnes of contained metal.

The expanded resource base follows a Phase 1 re-assay program of 3,271 historical aircore and diamond drill pulp samples across the project's Block 1 and Block 2 zones. Block 1 now hosts 367.45 million tonnes at 50.3 ppm scandium for 18,475 tonnes of contained metal, while Block 2 accounts for 578.63 million tonnes at 49.9 ppm scandium containing 28,882 tonnes of metal. Rather than relying on new drilling, the company unlocked the additional tonnage from its existing historical database by identifying broad, near-surface mineralisation that extends beyond previous resource boundaries.

“This significant scandium resource upgrade is a clear signal that we continue to advance the project across multiple fronts in a systematic and accelerated manner. We've now established the world's largest publicly reported JORC compliant scandium resource, at a time when the commodity is under intense focus from governments and industry seeking to secure supply outside China. Holding the largest scandium resource in the world, alongside our proprietary Selectro™ Process, provides a genuine pathway for Mount Ridley to commercialise this resource together with our broader commodity base at Grass Patch.”

— Allister Caird, Managing Director & Chief Executive Officer

The scandium inventory is co-located with the project's existing critical mineral assets, which include a heavy rare earth resource of 122.56 million tonnes reported in March 2026 alongside extensive gallium inventories. Mount Ridley is advancing additional density testwork to support upgrading portions of the Grass Patch deposit to higher confidence resource categories, while a Phase 2 re-assay program is underway across the broader complex.

Read the full announcement: Significant Scandium Resource Upgrade