Fulcrum Lithium Expands Alkali Flats and Proves Acid-Free Lithium Extraction
Key Takeaways
- Fulcrum Lithium's second heap leach scoping test validated an acid-free extraction pathway for Alkali Flats, delivering lithium recoveries of 64%–79% while reducing aluminium, iron, magnesium, and manganese impurities by over 99% compared to sulfuric acid leaching.
- The company now holds two validated extraction pathways — acid leach at 93%–96% recovery and acid-free water leach at 64%–79% — providing genuine optionality for future prefeasibility and scoping study work.
- 41 new lode claims were staked on the eastern boundary, bringing the total project footprint to 698 lode claims across approximately 58km², targeting the shallowing higher-grade core identified in the maiden MRE geologic modelling.
- The higher-grade resource above the 700ppm lithium cut-off stands at 1.92Mt LCE at an average grade of 775ppm, with a future drill programme being planned to extend this higher-confidence core.
- Alkali Flats sits approximately 10km from Albemarle's Silver Peak — the only operating lithium mine in the United States — and 15km from American Battery Technology Company's Tonopah Flats project, within a proven Nevada lithium belt.
Alkali Flats takes a major step forward with expanded footprint and acid-free extraction success
Fulcrum Lithium (ASX: FUL) has delivered a dual-catalyst announcement on 1 October 2026, simultaneously expanding the Alkali Flats project’s claims boundary and reporting a second successful heap leach scoping test using an acid-free extraction method. The update signals a project maturing on two fronts at once: resource growth potential and processing optionality.
The claims expansion adds 41 new lode claims to the eastern boundary, bringing the total to 698 lode claims across approximately 58km². On the metallurgical side, the second round of calcination roast and water column leach testing returned lithium recoveries of 64% to 79%, with up to 68% extracted within the first 24 hours, improving on the prior roast and water leach result of 66%.
These results follow the maiden Mineral Resource Estimate (MRE) announced on 4 August 2026, which defined a total resource of 10.7Mt LCE — already described by the company as one of the largest lithium deposits in the United States.
The maiden resource at Alkali Flats had been building toward the 10.7Mt LCE figure through progressive Phase 3 drilling and resource modelling work across the Nevada basin, with earlier coverage detailing how the geological confidence thresholds were met ahead of the August 2026 announcement.
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Claims expansion targets the high-grade eastern trend
The 41 new lode claims were not staked arbitrarily. Fulcrum targeted the eastern boundary specifically because geologic and resource modelling from the maiden MRE identified a shallowing, higher-grade core projecting in that direction.
Key points from the expansion:
- Claims were positioned using lithium grade and structural trends from the MRE geologic modelling and the company’s basin exploration work since listing
- Total project footprint now stands at 698 lode claims across approximately 58km²
- Context on claims reshaping: for the 2026/2027 US Bureau of Land Management (BLM) maintenance year, claims were reduced from 802 to 657 by relinquishing areas without resource potential at the margins, before the 41 new claims were added
- The higher-grade portion of the resource above the 700ppm lithium cut-off is estimated at 1.92Mt LCE at an average grade of 775ppm
- A future drill programme is being planned to extend this higher-confidence, higher-grade core
Figure 1 (Claims Extension Location map) in the source announcement shows the geographic position of the newly staked claims relative to the existing project boundary. Figure 3 shows the claims extension in relation to both the resource classification and the plan view of estimated lithium grades in the MRE block model, illustrating how the new claims are positioned to capture the eastward projection of higher-grade material.
Second heap leach test delivers acid-free extraction with dramatically lower impurities
The technical centrepiece of this announcement is the second heap leach scoping test, which validated an acid-free extraction pathway for Alkali Flats lithium clay material.
How the test works — a beginner-friendly explainer
Heap leaching is a process where crushed material is stacked and a solution is dripped through it to dissolve and extract target metals. Most lithium clay projects have explored sulfuric acid as the leaching solution because of its high extraction efficiency.
Calcination roast is a step that comes first: crushed clay pellets are heated at high temperature to transform the lithium mineralogy into a form that can be extracted more easily. The key distinction in this test is what happens next. Instead of sulfuric acid, Fulcrum used deionised water (water with minerals removed) as the leaching solution. This is what “acid-free extraction” means in practice.
Why does this matter to you as an investor? Lower reagent costs, a simpler processing flowsheet, a lower environmental footprint, and broader processing optionality at the prefeasibility study stage. Crucially, a cleaner leachate (the solution carrying dissolved lithium) means simpler and cheaper downstream processing to produce a battery-grade lithium product.
Results that validate the processing pathway
Three composite samples from drill holes AF2-2, AF2-5, and AF2-10 were selected across Zones 2, 6, and 8. Clay samples were pulverised and pelletised with a 5:1:1 blend ratio of sample, gypsum, and limestone, then roasted at 1,000°C for one hour. One kilogram of pellets was placed in a 75mm diameter column under a deionised water drip for 8 days in a closed-circuit setup, with the leachate recycled as feed solution. Measurements were taken every 24 hours.
The elemental comparison below (Table 2 from the source announcement) illustrates the dramatically lower impurity levels achieved by the roast calcination water leach versus the prior sulfuric acid leach, for Zone 6 (AF2-5):
| Element | Roast Water Leach (mg/kg) | Sulfuric Acid Leach (mg/kg) | Reduction |
|---|---|---|---|
| Aluminium (Al) | 4 | 11,003 | -99.96% |
| Iron (Fe) | <1 | 22,192 | -100.00% |
| Magnesium (Mg) | 18 | 36,413 | -99.95% |
| Manganese (Mn) | <1 | 713 | -99.86% |
| Lithium (Li) | 552 | 654 | -15.57% |
The lithium reduction of -15.57% reflects the trade-off: water leaching extracts slightly less lithium than acid, but the impurity reductions across aluminium, iron, magnesium, and manganese exceed 99% in each case.
Additional results from the test programme:
- Recovery range of 64% to 79% across the three composite samples from Zones 2, 6, and 8
- Up to 68% of lithium recovered within the first 24 hours
- Improvement on the prior agitated beaker roast and water leach result: 66% recovery improved to 79%
- Highest recoveries trend toward the eastern, shallower, higher-grade zone of the deposit — the same area targeted by the new claims
- The lowest reagent blend ratio tested (5:1:1) achieved the highest recoveries, suggesting further optimisation potential exists at lower ratios of gypsum and limestone
- The final deionised water wash applied at hour 192 added 7%–10% additional lithium recovery, indicating that open-circuit testing (where fresh deionised water is applied daily rather than recycled) could improve results further
On processing optionality: the acid-free water leach results complement, rather than replace, the prior sulfuric acid mini-column results that achieved 93%–96% lithium recoveries. Fulcrum now has two validated extraction pathways with different trade-off profiles. Higher recovery is achievable via the acid pathway; dramatically lower impurities are achievable via the water leach pathway. Both will be considered when assessing potential process flows in future studies.
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Managing Director’s outlook and the path ahead
Scott Keenan, Managing Director
“Alkali Flats is rapidly developing into a genuine growth story for Fulcrum. Following our maiden resource of 10.7Mt LCE, already one of the largest lithium deposits in the United States, we are now focused on expanding the project, with a future drill program being planned to grow the higher-confidence, higher-grade core of the deposit, which already stands at 1.92Mt LCE above a 700ppm lithium cut-off.
Complementing this growth strategy, our metallurgical program continues to advance along multiple extraction pathways, with this round successfully demonstrating the feasibility of a second early heap leach feasibility test, which was an acid-free extraction that delivered far lower impurities.
Encouragingly, the highest recoveries trend to the shallower, higher-grade south-east of the deposit, the same area we are prioritising for resource growth and likely target focus for potential early pit locations.
Together, with the potential for an expanding resource and advancing metallurgy create a very exciting outlook for Alkali Flats.”
Three reasons this announcement strengthens the investment case:
- Resource growth vector: New claims staked on the eastern boundary, combined with a planned drill programme targeting the higher-grade core (1.92Mt LCE at 775ppm), create a clear near-term catalyst for resource expansion
- Processing de-risked: Two validated extraction pathways (acid leach at 93%–96% recovery; acid-free water leach at 64%–79% with over 99% impurity reductions) provide optionality for future prefeasibility and scoping study work
- Strategic geography: The project is located approximately 10km from Albemarle’s Silver Peak, the only operating lithium mine in the USA, and approximately 15km from the American Battery Technology Company’s Tonopah Flats project, positioning Alkali Flats within a proven Nevada lithium belt
The near-term forward plan for the project:
- Continue advancing the metallurgical programme, with a focus on detailed mineralogy mapping, high-resolution lithium distribution, advanced beneficiation techniques, and extraction optimisations
- Data from the Phase 2 metallurgical testing programme is being used as input for the ongoing testing and metallurgical programme planning on Phase 3 core and cuttings material
- Define drilling options to extend the higher-confidence, higher-grade portion of the resource above the 700ppm cut-off
- Conduct bulk sampling for metallurgy
Resource growth and processing advancement are tracking in parallel at Alkali Flats, with the shallower, higher-grade eastern zone emerging as the focal point for both. That convergence is what gives this announcement its weight.
Ready to Explore the Full Investment Case for Alkali Flats?
Fulcrum Lithium’s Alkali Flats project is advancing on two fronts simultaneously — a claims expansion targeting a higher-grade eastern zone and a validated acid-free extraction pathway delivering over 99% impurity reductions, all building on a maiden resource of 10.7Mt LCE, one of the largest lithium deposits in the United States.
With a planned drill programme and two complementary extraction pathways now de-risked, the project’s next catalysts are taking shape. Explore Fulcrum Lithium’s project profile and latest updates on Discovery Alert to assess how Alkali Flats fits your portfolio.