Lithium development company Critical Resources (ASX:CRR) report that it has produced an ‘exceptional’ grade, ‘low impurity’ coarse spodumene concentrate through metallurgical testwork at the Mavis Lake Lithium Project in Canada.
The company says the scope of the first tranche of testwork was deliberately constrained to basic heavy liquid separation (HLS) and magnetic separation. The purpose of this testwork was to provide a preliminary indication of the lithium beneficiation performance by utilising dense media separation (DMS).
Critical Resources notes that the HLS testwork was undertaken by SGS Canada at their Lakefield facility in Ontario, with supervision in Australia by technical consultants MineScope Services. The sample suite for the testwork program was focused on representative samples from the Mavis Lake mineralised zone.
“The initial concentrate results are excellent, highlighting the growing potential and significant opportunity for the development of Mavis Lake”
A total of 50 quarter-and-a-half core samples from 7 drillholes were selected to provide a wide range of spatial locations, lithia grades, lithologies, spodumene intersection depths, and account for ‘typical’ mining dilution.
The company says the samples were delivered to SGS and compiled to create 2 composites, with the first being a representative grade composite of 1.2% Li2O, and the second being a ‘high-grade’ composite of 1.6% Li2O.
Commenting on the testwork, Critical Resources Managing Director Alex Cheeseman said: “The initial concentrate results are excellent, highlighting the growing potential and significant opportunity for the development of Mavis Lake.
Metallurgical testwork is a key strip in advancing Mavis Lake along the development pathway. The results show that the high-grade mineralisation at Mavis Lake, readily converts to high-grade, low impurity concentrate. Concentrate with this type of specification, commands a premium in the market.
This has been achieved through a very simple flowsheet that has the potential to enhance project development and delivery opportunities by being low impact, low risk and low cost.”
Critical Resources reports the HLS and magnetic separation test results demonstrate consistently ‘high’ lithium grades, and ‘low’ iron oxide impurities across all test streams.
The first tranche of testing was deliberately constrained to basic HLS and magnetic separation, with subsequent optimisation and floatation testwork now being scheduled. The HLS results also show a ‘strong’ potential to use DMS as the primary beneficiation method.
The company reports further metallurgical testwork is being scheduled to test the full potential of lithium liberation from Mavis Lake feed material. This may include HLS testwork at finer crush sizes, as well as floatation of ground middlings and tailing from raw material crushing and HLS processing.
Critical Resources reports it has also begun permitting to allow bulk sample collection, and expects to undertake this work during the Canadian summer.
These bulk samples will allow for the conduct of further additional, and extensive testwork programs aimed at optimising and rigorously testing future flowsheet design. The company says the results of this testwork will form the basis of a Scoping Study for the project expected to be completed in mid-2023.
Critical Resources is an Australian lithium development company focused on developing its flagship Mavis Lake project, located in Ontario Canada. Other projects held by the company in Canada include the Graphic Lake, Plaid, and Whiteloon Lake projects.
The company also holds the Halls Peak Base Metals Project in New South Wales, as well as the Sohar Copper Project in northern Oman.