ASX Announcement — 6 August 2026
Mount Ridley Mines Limited (ASX: MRD; OTCID: MRDMF) has reported the first automated mineralogy study on material from the Grass Patch Complex, approximately 25km north of the deepwater port of Esperance in Western Australia.
The TESCAN Integrated Mineral Analyzer study provides direct evidence of how rare earth elements occur within the deposit—an important input into the processing flowsheet being developed alongside Phase 1 metallurgical testwork.
Three phosphate hosts identified
- Xenotime, a potential host for valuable heavy rare earths, was the most common phosphate mineral identified.
- Crandallite-group phosphates and monazite/rhabdophane were also recorded.
- The phosphate minerals are fine grained and closely associated with clay in the shallow, weathered Grass Patch regolith.
Because the rare earths occur in discrete phosphate minerals rather than only being loosely adsorbed onto clay surfaces, the results support investigating physical concentration before leaching. Mount Ridley said flotation could reduce the volume of material passed into downstream extraction, although further testwork is required to establish achievable grades and recoveries.
Next steps
The company plans bench-scale flotation testing across a range of grind sizes, in parallel with its broader metallurgical program. The work is intended to assess concentrate grades and recoveries and inform the beneficiation stage of the Grass Patch processing strategy.