Flotation tests bump Big Whopper recoveries

Bench-scale mineral dressing tests on 100-kg samples from the Separation Rapids pegmatite deposit in northwestern Ontario indicate lithium recoveries and grades that are comparable to the high-quality concentrates currently available from established producers.

The flotation tests, done by Lakefield Research for property holder Avalon Ventures (AVL-V), produced a high-grade concentrate of petalite (lithium aluminum silicate), grading 4.75% to 4.85% lithium oxide (LiO2), and a low-grade concentrate with 4%. The flotation circuit tested by Lakefield recovered about 90% of the LiO2 in the rock.

The two concentrates, when combined, grade an average 4.3% LiO2, which is equivalent to widely available concentrates on the world market. Southern African lithium producers routinely deliver a 4.2% concentrate. Petalite concentrates are used to produce lithium salts in the fine-chemical industry and as feedstocks in the glass and ceramic industries.

Consulting firm Micon International is revising an earlier economic analysis of the project to take account of the new beneficiation data. The new analysis will also update the current market conditions for lithium production. Lakefield is now turning its attention to feldspar recoveries from the pegmatite material; the rock’s potassium feldspars are potentially economic sources of rubidium metal.

For its part, Avalon plans to carry out bulk sampling, beginning this fall. An access road is being pushed in and the company has put the sampling work out for bids from mining contractors.