Read our latest MRD research: Selectro and the Western Scandium Supply Chain, 8 October 2026.
This announcement adds evidence to the report's third-party processing thesis. Below, we explain what it advances and what remains unproven.
ASX announcement: 21 October 2026
Mount Ridley's first third-party bauxite test now has its missing result. Mount Ridley Mines (ASX: MRD) says its wholly owned, patent-pending Selectro process extracted 94.9% of the gallium from a composite supplied by Australian Silica Quartz Group (ASX: ASQ).
That adds gallium to the 91.9% aluminium and 96.7% iron extraction reported on 15 October. All three results come from the same single leach, operated below 100°C. This is an additional assay result from that test, not a second successful test.
For MRD, the significance is straightforward: Selectro is showing potential beyond the company's own Grass Patch material. The next challenge is turning those dissolved metals into separate, purified products.
How this affects our latest research
Our 8 October research update framed Selectro as a potential Western processing route, rather than simply a way to extract metals from MRD's own deposit. The first milestone in that report was to publish results on suitable third-party feed beyond the Grass Patch composite.
The 15 October aluminium and iron results provided the first evidence against that milestone. Today's gallium assay completes the picture for that same bauxite test: Selectro extracted three targeted metals above 90% from material supplied by another company. That supports the possibility of applying the chemistry to third-party feeds, but it does not yet establish repeatability across deposits or a licensing business.
Gallium also adds useful context to a trade-off highlighted in our research. On Grass Patch material, gallium recovery fell to 41.5% at the lower reagent dose used in Test 3, compared with 55.8% in Test 2. The 94.9% bauxite result is encouraging evidence on a different feed, not proof that the Grass Patch trade-off has been resolved. Different mineralogy and reagent formulations mean those percentages are not directly comparable.
The valuation distinction is important. The 8 October report maintained a speculative A$0.144 target using A$4,000 per tonne of contained scandium and assigned zero value to Selectro licensing. Those are the dated report's assumptions, not a new valuation in this article. The bauxite gallium result does not add scandium tonnes to the Grass Patch resource or, on its own, justify increasing that target. We have not recalculated the valuation or issued a revised rating here.
What changes is the evidence supporting a processing opportunity that the report did not value. What remains is the harder part of the research checklist: separation into saleable products, pilot-scale performance, complete mass balances, defensible costs and funded commercial adoption. MRD's stated shift towards separation and purification is therefore directly relevant to the next milestone, rather than confirmation that it has already been achieved.
What the test actually showed
The bauxite composite was prepared from 16 vacuum drill samples across four holes at ASQ's Athena and Ceres prospects in Western Australia's Darling Range. Its reported head grades were 80 parts per million gallium, 41.9% aluminium expressed as Al₂O₃ and 13.6% iron expressed as Fe₂O₃.
- Gallium: 94.9% extraction to solution.
- Aluminium: 91.9% extraction to solution.
- Iron: 96.7% extraction to solution.
Gallium required the more sensitive ICP-MS assay method because of its low concentration in the feed. MRD says the recoveries were calculated from solution assays and calculated head grade.
That definition matters. A 94.9% leach recovery does not mean 94.9% of the gallium has been converted into saleable metal. Separation, purification and any subsequent processing can introduce further losses and costs.
Why gallium changes the discussion
Bauxite is best known as the feedstock for aluminium. It is also the main source of primary gallium, a material used in gallium arsenide and gallium nitride semiconductors for applications including communications, defence systems and power electronics.
MRD's announcement, citing the US Geological Survey, says China accounts for approximately 99% of global primary low-purity gallium production. That concentration helps explain the interest in alternative sources. It does not, by itself, establish a market or customer for Selectro.
The company compares its result with approximately 70% gallium extraction into liquor in the conventional Bayer process, citing an ICSOBA technical paper. It also notes that recovering gallium from Bayer liquor requires a dedicated circuit.
The comparison is encouraging, but it is not a like-for-like commercial plant trial. One Selectro composite test cannot establish lower total costs, better overall product recovery or commercial superiority across different bauxite feeds.
A different residue, with more work to do
MRD says the leach left a silica-rich residue, with more than 90% of the silica remaining in that residue, rather than generating conventional Bayer red mud.
That could be an important part of the process story. But a different residue is not automatically a saleable by-product or proof of a lower overall environmental footprint. Residue handling, reagent recycling, water use and performance at larger scale still need to be assessed.
The next milestone is product separation
With gallium, aluminium and iron all extracted above 90% in this test, MRD says its immediate focus is moving to separation and purification pathways for both bauxite and Grass Patch feeds.
The announced next steps are:
- Separating and purifying gallium from the Selectro leach solution.
- Reporting results from a second bauxite test, which the company says is underway.
- Testing additional third-party feedstocks.
- Progressing the design and construction of a Selectro demonstration plant.
Those are planned activities, not completed milestones. Product purity, repeatability, reagent consumption, operating costs, funding and scale-up will matter as much as the headline extraction percentages.
The Cashu view
Relative to our 8 October research, this is progress on the third-party feed milestone, not a completed commercialisation case. The gallium assay strengthens the multi-metal processing opportunity alongside the earlier aluminium and iron results, while leaving the resource-based valuation unchanged in this article.
Our focus now moves to the next steps already identified in that report: usable products, repeatable performance at larger scale and credible economics. Evidence on those points would be more meaningful for assessing potential licensing value than another headline leach percentage alone.
Source and related research
- Read the original MRD ASX announcement, 21 October 2026: Selectro Returns 95% Gallium Recovery from Bauxite. Technical results, process descriptions and planned activities above are attributed to this release. Its market and Bayer-process comparisons draw on the references listed in the announcement.
- Our 15 October coverage: the aluminium and iron results from the same bauxite test.
- Cashu Research Report: Selectro and the Western Scandium Supply Chain.
General information only, not personal financial advice or a recommendation to buy or sell MRD shares. Laboratory results and planned development activities do not establish commercial viability. Investments can lose value.