Mount Ridley's Metallurgy Breakthrough Boosts Rare Earth Prospects
A comprehensive review by Mount Ridley Mines of historical metallurgical test work at its Grass Patch project near Esperance in Western Australia has confirmed an outstanding leach response, with heavy rare earth recoveries reaching as high as 86.5 per cent. These impressive results were achieved under conventional hydrochloric acid leach conditions, providing a clear green light for further investigation and development.
Exceptional Upgrades and Magnetic Rare Earth Potential
The metallurgical success extends beyond leaching. Initial screen beneficiation test work delivered remarkable outcomes, including a standout 200 per cent total rare earth oxide (TREO) upgrade at the Vincent prospect. Additionally, the Mia and Jody prospects provided an excellent average upgrade of 164 per cent. Magnetic rare earths also show strong potential, with recoveries of neodymium and praseodymium hitting a substantial 85.2 per cent.
These findings have given Mount Ridley confidence that it can significantly enhance the feed grade before material even reaches the leach tanks, simply by screening out barren material. This approach may offer major bottom-line savings for the company, improving overall project economics.
Unique Geology and Heavy Rare Earth Advantages
Mount Ridley's consistent, high extraction results for heavy rare earths such as dysprosium and terbium, particularly at the Winston, Vincent, and Jody prospects, highlight a major project advantage. The company attributes this superior metallurgical performance to the project's mafic-dominated geology, which ensures mineralisation is compatible with standard hydrometallurgical processing. This provides a potentially significant cost-competitive edge in the sector.
Interestingly, Mount Ridley has discovered that the more valuable heavy rare earth elements leach more effectively than their light rare earth counterparts. This unique characteristic sets the Grass Patch project apart from typical regolith-hosted systems, offering a distinct operational benefit.
Recent Resource Milestone and Global Implications
This metallurgical breakthrough follows closely on the heels of a significant milestone in late March, when Mount Ridley unveiled a new inferred resource of 122.56 million tonnes grading 889 parts per million (ppm) TREO, containing 108,954 tonnes of TREO. Notably, 44,610 tonnes of this is in the heavy rare earth (HREO) basket, giving the resource an impressive 41 per cent HREO ratio.
With the global supply of heavy rare earths largely dominated by China, Mount Ridley is positioning itself as a vital player in the emerging Australian and allied strategic metals supply chain. The company aims to leverage these test results as a strong technical foundation for ongoing metallurgical optimisation and flowsheet development, potentially including the recovery of valuable by-products like scandium and gallium.
Future Outlook and Strategic Momentum
Mount Ridley is steadily advancing as it transitions into the next phase of metallurgical optimisation. With high recoveries and a clear development path, momentum is firmly running in the company's direction. The new findings from historical samples demonstrate that sometimes the most valuable insights can be unearthed from existing data, offering a promising outlook for the project's future.
