Mount Ridley Mines Limited has confirmed through automated mineralogy that rare earth elements at its Grass Patch project in Western Australia are hosted within discrete phosphate minerals.

The study, conducted using the TESCAN Integrated Mineral Analyzer (TIMA), identified three specific phosphate hosts: xenotime, crandallite group phosphates, and monazite/rhabdophane. These findings provide critical technical insight for the company, as the mineralogy dictates the most effective processing approach for the project’s regolith-hosted material.

By confirming that the rare earths are contained in these minerals rather than simply adsorbed onto clay surfaces, the company has identified a potential pathway to use flotation to concentrate the material before leaching. This process could reduce the total volume of ore requiring intensive leaching, potentially enhancing the efficiency of the overall extraction flowsheet.

The company has transitioned its focus at Grass Patch from resource definition toward metallurgical characterisation and beneficiation strategy throughout the middle of 2026. This move aligns with Mount Ridley's broader corporate objective of diversifying its capabilities by pursuing downstream processing pathways for critical minerals, supplementing its primary upstream exploration activities.

“The TIMA results inform us exactly how the rare earths sit in our deposit. Some of our peers have had outstanding results applying flotation to comparable regolith hosted HREE deposits and these results provide a basis for MRD to investigate a similar beneficiation pathway. We're excited about the prospect of flotation to concentrate our ore and results from that work will dovetail into the outcomes from our Phase 1 metallurgical testwork, which we look forward to updating our shareholders on shortly.”

— Allister Caird, Managing Director & CEO

Mount Ridley is now fast-tracking liberation and flotation testwork across various grind sizes to assess achievable concentrate grades and mineral recoveries. These findings will be integrated into the broader, ongoing Phase 1 metallurgical testwork program, with results expected to be released shortly.

Read the full announcement: Grass Patch Rare Earths Confirmed to be Hosted in Phosphates