Core Lithium Ltd (ASX:CXO) has improved metallurgical performance in the final phase of test work on the BP33 deposit within the Finniss Lithium Project near Darwin in the Northern Territory.
Dense media separation (DMS) test work on spodumene pegmatite has shown that a 6.0% lithium oxide concentrate can be produced at an overall lithium recovery of 71% at a coarse 6.3-millimetre crush size.
A definitive feasibility study (DFS), released in April 2019, was based on the production of a 5.5% Li2O concentrate at 72% recovery.
These updated results indicate an improvement in the concentrate grade of 9% for little decrease in recovery.
Notably, iron grade in the combined concentrates was 0.42% iron oxide, well below the recognised maximum of 1%.
In high demand
Core believes that the high-quality, low-iron, coarse Finniss lithium concentrate will be preferred in a lithium battery and EV market focused on demand for exceptional quality materials supplied from ethical and sustainable sources.
Importantly, production of high-quality lithium concentrate by DMS avoids the much higher capital, financing and operating costs associated with flotation processing.
Capital efficient project
The 2019 DFS highlighted annual production of 175,000 tonnes of high-quality lithium concentrate at a C1 opex of US$300/tonne and US$50 million capex through simple and efficient DMS (gravity) processing.
Capital efficient processing and close proximity to the city and port of Darwin means that Core could be one of the most cost-competitive lithium producers in Australia.
By-products and fines
The potential for producing meaningful quantities of lithium fines and feldspar by-products has also been confirmed by these latest results.
Core’s transport cost from mine to port is only US$7/tonne, so by-products produced at marginal cost could add to project profits.
The 0.85-millimetre lithium fines had a grade of 1.2% lithium oxide and represent approximately 20% of the plant feed mass, or 200,000 tonnes per annum.
The feldspar potential contained 14-15% sodium oxide and potassium oxide with very low iron of less than 0.05% iron oxide.
This represents around 10% of plant feed mass or 100,000 tonnes per annum.
Feasibility study update
The new metallurgical results will be incorporated along with new mineral resource and ore reserve estimates into an updated feasibility study, which is expected later this quarter.
This study is targeting a significantly increased mine life and substantially improved project economics.
With project approvals to construct and operate now secured and a substantially increased mine life expected, Core believes the project is positioned to be at the front of the line of new global lithium supply as EV manufacturing recovers post COVID-19.