Mount Ridley reveals bigger Grass Patch opportunity as Selectro recoveries improve

Grass Patch resource scale expands sharply

Mount Ridley Mines Limited (ASX:MRD) is presenting Grass Patch as a large, multi-commodity system, but the more consequential number arrived after the reporting year ended: its inferred scandium resource rose from 367.98 million tonnes in January to 946.1 million tonnes at 50.1 parts per million in August. The expanded estimate contains approximately 47,357 tonnes of scandium metal, although its inferred classification does not establish economic viability.

The project also carries an inferred gallium resource of 838.7Mt at 29.3ppm, containing about 24,584 tonnes of gallium metal, alongside a 122.5Mt rare earth oxide resource at 889ppm total rare earth oxides. Heavy rare earth oxides account for about 41% of the contained TREO, including approximately 4,272 tonnes of dysprosium oxide and 719 tonnes of terbium oxide. The company says these resources overlap within the same weathered regolith profile, creating the basis for evaluating a combined processing route rather than separate commodity projects.

Selectro moves from concept towards testwork

The technical question is whether that geological scale can survive contact with a processing plant. Mount Ridley’s Selectro process produced its most encouraging reported results in September, with scandium recovery of approximately 92% and average heavy rare earth recovery of approximately 84%. Individual heavy rare earth recoveries reached as high as 86%, while the company said reagent use was roughly half that used in earlier tests.

Those figures come from laboratory testwork, not a commercial operation. Gallium recovery in the latest test was approximately 41.5%, below the earlier Selectro results shown in the report, and the company itself identifies scale-up and economic viability as material risks. The process has patent-pending protection, but the next test is less glamorous and more important: whether the recovery profile, reagent consumption and mineral separation performance hold through flotation, bulk samples and larger-scale work.

Capital funds the next technical phase

Mount Ridley ended FY2026 with a net loss of AUD 2.38 million and net operating cash outflow of AUD 1.90 million, compared with AUD 2.64 million and AUD 1.02 million respectively in the prior year. Cash at 30 June was AUD 1.89 million, helped by AUD 2.96 million in share proceeds during the year. The balance sheet therefore describes an explorer with a larger technical ambition, not a self-funding developer.

A subsequent September placement raised AUD 2.0 million before costs through approximately 60.6 million shares at AUD 0.033 each, with directors committing a further AUD 100,000 subject to shareholder approval. The funds are earmarked for flotation and bulk metallurgical testwork, scoping studies, resource definition and further Selectro optimisation. The annual report says management forecasts support a positive cash balance over the next 12 months, while also retaining the ability to defer or reduce discretionary exploration spending.

The development hurdle remains unresolved

Grass Patch spans more than 1,069 square kilometres, with the company estimating that about 80% remains untested. A Phase 1 re-assay program covering 3,271 historical air-core pulp samples found scandium outside existing resource boundaries, including 22 metres at 134.09ppm Sc₂O₃ from 33 metres in hole MRAC0977. These results support further exploration, but they also widen the amount of ground and data that must be converted into a coherent development case.

For shareholders, the tension is now clear. Mount Ridley has assembled substantial inferred inventories, improved selected laboratory recoveries and secured near-term funding, yet it has not demonstrated a commercially viable flowsheet, completed a scoping study or moved into production. The next round of bulk and flotation work will have to show whether Selectro is merely impressive in a table of recoveries or useful in the harder arithmetic of capital, operating costs and product quality.