Jindalee hoists exceptional lithium extraction results from McDermitt ore acid leaching
Special Report: Jindalee Lithium’s metallurgical testing has proved rewarding, demonstrating that beneficiated ore from its McDermitt project in Oregon is readily amendable to acid leaching.
McDermitt holds the crown as the largest lithium deposit in the US by contained lithium with a resource of 3Bt at 1,340 parts per million (ppm) for 21.5Mt lithium carbonate equivalent, somewhat larger than Lithium America’s advanced 19.1Mt Thacker Pass asset, 30km away.
While this is significant by any standard, Jindalee Lithium (ASX:JLL) is certainly not resting on its laurels and is waiting on the US Bureau of Land Management’s (BLM) crucial National Environment Policy Act (NEPA) process to approve its exploration plan of operations (EPO).
Beneficiation test work carried out last year also achieved 92% lithium recovery and 25.3% mass rejection, increasing the average grade to leach up to 2,107ppm lithium, 18% higher than the average head grade of previously reported metallurgical samples and 57% higher than the average resource grade.
Work is also progressing on a pre-feasibility study, which will leverage the baseline environmental studies and Native American heritage investigations undertaken for the EPO.
Acid leaching of the beneficiated material has now returned excellent results with lithium extractions of 93% and 94% achieved from both the 250µm and 75µm leach feeds using 500kg sulphuric acid per tonne of leach feed.
The 250µm leach feed was also subjected to a higher strength (850kg) acid leach that returned a higher extraction rate of >98.5%.
Adding further interest, while the leach test work extended for up to four hours, most of the lithium extraction occurred in the first hour.
Optimised lithium extraction and acid addition rates will be incorporated into the PFS, with leaching of a bulk composite also under way to provide lithium in solution for downstream test work.
Beneficiated ore samples have also been shipped to South Korea’s POSCO for parallel leach test work. Jindalee has in place a MoU with POSCO – a major lithium chemical producer – to investigate test work for the optimal lithium extraction from McDermitt ore. Jindalee and POSCO will evaluate commercialisation opportunities for McDermitt at the completion of the test work activities.
This article was developed in collaboration with Jindalee Lithium, a Stockhead advertiser at the time of publishing.
This article does not constitute financial product advice. You should consider obtaining independent advice before making any financial decisions.