Processing Challenges Remain Despite Strong Lithium Recovery at Alkali Flats
Fulcrum Lithium’s latest metallurgical tests at Alkali Flats reveal lithium recovery rates exceeding 90% with promising low-temperature, short-duration leaching methods, expanding processing flexibility ahead of Phase 3 core analysis.
- Up to 96% lithium recovery in acid-cured mini-column leach tests
- Over 80% lithium extracted within 72 hours at ambient temperatures
- Water leaching after roasting yields up to 66% lithium recovery
- Hydrocyclone and alcohol screening enhance grade and reduce carbonates
- Phase 3 core metallurgical testing underway to refine heap leach process
High Lithium Recovery Achieved with Low-Temperature Methods
Fulcrum Lithium Ltd (ASX:FUL) has reported encouraging metallurgical results from its Alkali Flats lithium claystone project in Nevada, with lithium recoveries ranging from 93% to 96% in seven-day acid-cured mini-column leach tests. Notably, the tests achieved over 80% lithium extraction within just 72 hours at ambient temperatures, signalling potential for fast, low-cost processing routes.
Complementing these findings, water leaching after roasting samples with optimised blends of gypsum and limestone delivered lithium recoveries between 57% and 66% in only one hour at ambient conditions. This adds a viable alternative to the previously successful sulfuric acid leaching process, broadening the project’s processing flexibility.
Beneficiation Techniques Improve Grade and Reduce Acid Consumption
Beneficiation tests conducted by Kappas Cassiday and Associates (KCA) demonstrated that hydrocyclone separation could reduce sample mass by up to 41%, remove over half the carbonates; which are major acid consumers; and increase lithium grade by up to 27%. Alcohol screening also showed promise, cutting mass by up to 15%, reducing carbonates by 30%, and boosting grade by 12% in some samples.
The combination of these beneficiation methods with leaching processes could significantly lower processing costs by reducing reagent consumption and improving lithium concentrate quality, a crucial consideration for claystone-hosted lithium deposits.
Phase 3 Core Testing to Refine Heap Leach Processing
Building on these scoping metallurgical results from Phase 2 reverse circulation (RC) drill cuttings, Fulcrum has commenced further test work on core samples from its recently completed Phase 3 drilling program. This next phase aims to refine a low-cost heap leaching processing pathway, leveraging the project’s extensive drilling dataset.
The Phase 3 program, which significantly increased drill density across the Alkali Flats project area, has already confirmed thick, continuous lithium mineralisation in multiple holes, supporting the upcoming maiden Mineral Resource Estimate. The metallurgical data from this core testing will be critical to validate and optimise processing flowsheets for eventual commercialisation thick continuous lithium mineralisation.
Strategic Location Near Established US Lithium Operations
Alkali Flats covers approximately 66 square kilometres in Esmeralda County, Nevada, situated close to prominent lithium projects such as Tonopah Flats and TLC, as well as the Silver Peak mine, the only operating lithium mine in the United States. This favourable location within a mining-friendly jurisdiction enhances the project’s strategic value.
Fulcrum’s ongoing drilling and metallurgical programs, including the recent expansion of the project area and accelerated Phase 3 campaign, align with broader efforts to secure domestic lithium supply amid rising global demand. The company’s approach to exploring multiple processing pathways reflects an adaptive strategy to unlock value in its lithium claystone resource accelerated Alkali Flats drilling.
Bottom Line?
Fulcrum’s metallurgical advances at Alkali Flats highlight promising low-cost lithium extraction options, but the scalability and economic feasibility of these methods await confirmation from ongoing Phase 3 core testing.
Questions in the middle?
- How will Phase 3 core metallurgical results influence the final processing route selection?
- What are the anticipated capital and operating cost implications of the heap leaching pathway?
- Can the beneficiation methods demonstrated be scaled effectively in commercial operations?
