• Metallurgical sampling at JRL’s McDermitt project have returned an average head grade of 0.179% Li or 1,790ppm
  • 34% higher than the average grade of the current McDermitt Indicated and Inferred resource grade
  • Excellent potential to process shallow, higher grade ore early in the mine life, “with positive implications for project economics”
  • Beneficiation work to separate the lithium fractions prior to acid leaching is now underway


Initial head grades averaging 1,790ppm lithium – about 34% higher than the resource grade of 1,340ppm – have been received from metallurgical samples at the McDermitt lithium project in Oregon, USA.

Jindalee Resources (ASX:JRL) acquired the McDermitt lithium sediment project, on the Oregon-Nevada border in the US, in 2018 after an extensive search across the western United States.

A lot of work has been done since then, with an updated resource at the project resulting in a combined Indicated and Inferred inventory of 3 billion tonnes at 1,340ppm Li for a total of 21.5Mt LCE in late February this year.

The project is now the largest lithium deposit in the US by contained lithium – the closest analogy to the project being US$1bn capped Lithium America’s advanced 19Mt Thacker Pass asset, 30km away.


Potential to process shallow, higher-grade ore

Head assays received for McDermitt metallurgical samples being tested by consultant metallurgists, Hazen, have returned samples averaging 0.179% Li (1790 ppm), demonstrating the potential to process shallow, higher-grade ore early in the mine life.

These results also have positive implications for overall project economics, JRL says, with head assays reflecting a 34% increase than the average grade of the current McDermitt Indicated and Inferred resource.

EPCM company and managers of the testwork program, Fluor Corporation, reviewed metallurgical testwork undertaken at McDermitt in March 2023, determining that acid leaching with ore beneficiation (to upgrade the leach head grade) delivered the lowest operating costs and best financial outcome among the alternatives considered.

Fluor also noted that the very large resource at McDermitt allows flexibility in development, providing the opportunity to optimise mining and feed higher grade ore early in the mine life.

Fluor recommended that a comprehensive metallurgical testwork program be undertaken to provide information upon which the preferred flowsheet for the processing of McDermitt ore can be defined.

Results from the particle size distribution testwork on samples are now being reviewed.

Attrition scrubbing to beneficiate the ore and separate the lithium rich finer grained fractions prior to acid leaching is also currently underway, with results to be reported once available.



This article was developed in collaboration with Jindalee Resources, 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.