Mount Ridley Mines Files Selectro Patent After Heavy Rare Earth Recoveries Reach 83%

Highlights

• Selectro hydrometallurgical process recovered up to 83% heavy rare earths, 80% scandium, and 56% gallium from Western Australia's Grass Patch material
• Recovery rates significantly outperformed baseline HCl leaching, which recovered no gallium and only 25% scandium
• Grass Patch hosts substantial reported resources: 122.5 Mt at 889 ppm TREO, 367.98 Mt scandium, and 838.7 Mt gallium
• Provisional patent secures a priority date but does not confirm the process is patentable, scalable, or economically viable
• Source article was developed in collaboration with Mount Ridley as an advertiser, warranting additional investor scrutiny

Mount Ridley Mines (ASX: MRD (opens in a new tab)) has filed a provisional patent for its Selectro hydrometallurgical process after tests on Western Australia's Grass Patch material recovered up to 83% heavy rare earths, 80% scandium, 77% light rare earths, and 56% gallium. The numbers reported (opens in a new tab) via The Australian are intriguing—particularly for dysprosium and terbium—but investors should remember what the promotional headlines blur: Selectro remains an early-stage process requiring scale-up, reagent optimization, and economic validation.

REEx Insight: The Ore Is Only Half the Battle

Rare earth investors obsess over tonnes and grades. Increasingly, the real intellectual property sits in the flowsheet. Selectro matters because Mount Ridley is attempting something commercially attractive: extract rare earths, scandium, and gallium from one feed stream while recycling reagents. Comparative testing reportedly recovered 77–83% heavy REEs versus substantially lower recoveries using baseline hydrochloric-acid leaching, while scandium reached 80% versus 25%. Baseline HCl recovered no gallium.

That is encouraging. It is not yet a processing revolution.

Patent Filed, Economics Pending

Grass Patch provides genuine scale: reported resources include 122.5 Mt at 889 ppm TREO, 367.98 Mt at 57.3 ppm Sc₂O₃, and 838.7 Mt at 29.3 ppm gallium. Earlier Mount Ridley drilling also established laterally extensive REE mineralization near Esperance.

But the source article comes with an unusually important disclosure: Stockhead developed it in collaboration with Mount Ridley, an advertiser. Claims such as "superiority," lower costs, and environmental advantages therefore deserve investor scrutiny until demonstrated through larger-scale engineering and economic studies. The provisional patent protects a priority date; it does not establish that the technology is patentable, scalable, or profitable. Bulk testing now becomes the real examination.