Mount Ridley Mines Limited has reported initial metallurgical testwork results for its proprietary Selectro™ Process, achieving heavy rare earth element recoveries of 77% to 83% from unbeneficiated drill samples at the Grass Patch Complex in Western Australia.

The testwork, conducted by independent laboratory Nagrom, evaluated recoveries across heavy rare earths, light rare earths, scandium and gallium from a single composite sample. The Selectro™ Process more than doubled the average recovery of the industry-standard hydrochloric acid leach across the tested elements, achieving a scandium recovery of 80% and an average gallium recovery of 56%, while comparative hydrochloric acid leaching recovered zero gallium.

The technology is designed as a closed-loop system using lower-cost reagents than conventional hydrochloric acid methods. The Grass Patch Complex hosts significant critical mineral inventories, including an Inferred Mineral Resource of 367.98 million tonnes at 57.3 ppm scandium and 838.7 million tonnes at 29.3 ppm gallium.

Mount Ridley recently appointed Chris Larder as Chief Technology Officer in July 2026 to bring ownership of the company's processing route in-house as it advances from resource definition into development.

“These are the first metallurgical testwork results the Company has produced since the definition of our HREE, scandium and gallium mineral resources and the establishment of the current management team and corporate strategy. The Selectro™ Process results validate what we believed to be true about Grass Patch, that we have a genuinely polymetallic system where all three critical minerals can be recovered from a single leach process. We look forward to providing further updates in due course.”

— Allister Caird, Managing Director & CEO

Ongoing metallurgical testwork programs remain focused on beneficiation, process optimisation, reagent recycling, and downstream product development.

Read the full announcement: MRD Proprietary Leach Tech Delivers Standout Results