Jindalee Resources Limited (ASX:JRL) has returned lithium leaching recoveries of up to 97% in recent test work at its McDermitt Lithium Project on the Nevada-Oregon border.
In September 2018 Jindalee completed four vertical diamond holes to an average depth of 90 metres drilled in order to gain a better understanding of the thickness and grade of lithium mineralisation recognised from previous surface sampling.
This information was used in the estimation of an exploration target, which demonstrated that the McDermitt project has the potential to host one of the largest lithium deposits in the USA.
Subsequent metallurgical tests have now also confirmed the amenability of the lithium-rich sediments to sulphuric acid leaching with high lithium recoveries achieved over short time frames.
Lithium extraction over time from the most recent sulphuric acid leach testing.
Test work and results
Sulphuric acid leaching at various experimental conditions was conducted in February and March 2019 with the most recent test involving the addition of sulphuric acid in a heated and agitated environment.
Schematic cross section showing significant intersections and geology.
More than 90% of the available lithium reported to the leach solution in four hours, and 97% lithium extraction was achieved after 11 hours while consuming 506 kilograms of sulphuric acid per tonne of ore.
The high recoveries achieved in these early-stage tests provide further encouragement for Jindalee to continue to progress work at McDermitt and compare very favourably with those published for similar sediment-hosted lithium projects.
The company will undertake additional tests aimed at optimising the leach parameters and reducing sulphuric acid consumption while producing a leachate amenable to subsequent processing.
This testing will include beneficiation of the ore, removal of acid robbing phases such as carbonates, changes to the amounts and timing of heating and acid additions and alternate leach pathways.