Locksley Resources (ASX: LKY) hits 68% antimony concentrate—could this mark the rebirth of U.S. supply?

Locksley Resources Limited (ASX: LKY, OTCQB: LKYRF, FSE: X5L) is fast emerging as one of the most closely watched junior explorers in the critical minerals sector after unveiling a series of major technical and operational milestones across its Mojave Project in California. The Australian-listed company announced a fourfold expansion of the Desert Antimony Mine’s mineralised corridor, produced a 68.1 percent high-grade antimony concentrate nearing theoretical purity, and secured regulatory approval to begin an enlarged drilling campaign. The developments mark a decisive step in its ambition to deliver a 100 percent Made-in-America antimony supply chain amid Washington’s growing urgency to secure domestic sources of strategic minerals.

The Mojave Project sits in the shadow of MP Materials’ Mountain Pass Mine—the United States’ only producing rare earth operation—placing Locksley at the center of a region now viewed as critical to national resource independence. The company’s parallel advances in geological mapping, metallurgy, and permitting signal a shift from early-stage exploration to tangible development readiness, positioning it as a contender in the U.S. government’s broader effort to rebuild self-sufficiency in defence and energy-linked metals.

How is Locksley Resources expanding the Desert Antimony Mine strike length and what does a 400% increase mean for resource potential?

Locksley Resources has reported a dramatic expansion of its Desert Antimony Mine (DAM) structural corridor from 0.3 kilometers to 1.2 kilometers—a 400 percent increase in strike length that fundamentally changes the scale and geometry of the discovery. Structural mapping conducted in August and September confirmed continuity of the north-northeast striking shear zone hosting high-grade stibnite mineralisation and revealed a parallel zone approximately 150 meters to the west. Both zones exhibit comparable alteration and kinematic features, suggesting the potential for a multi-lode mineralised system that could support a district-scale resource base.

The company’s updated three-dimensional geological model, built from new surface mapping, defined seven priority targets for follow-up sampling and future drilling. The data indicate steep north-plunging intersections between shear zones and folded host rocks—interpreted as key controls on mineralisation. According to geological consultants, the size and structural coherence of the Mojave corridor align with the characteristics sought under U.S. programs such as the Defense Production Act Title III and the Department of Energy’s ARPA-E initiative, which prioritise clean, high-grade domestic feedstock for critical mineral processing.

At the Hendricks prospect, located about 2.5 kilometers southeast of DAM, initial grab sampling returned assays of up to 216 grams per tonne silver along with elevated zinc, lead, and copper values. Meanwhile, first-pass mapping at the Junipero prospect—just north of the Mountain Pass pit—identified multiple lamprophyre dykes interpreted as mantle-tapping structures that could host rare earth–bearing carbonatites. Together, these findings suggest Mojave may host not only one of the United States’ highest-grade antimony systems but also additional polymetallic and rare earth potential.

Chief Executive Officer Kerrie Matthews described the mapping campaign as a “step change in scale,” noting that the expanded target corridor “has effectively lit up the entire Mojave Project for polymetallic vein discoveries.” Industry observers interpreted her remarks as an early indication that the company could move quickly toward a JORC-compliant Exploration Target once the next sampling phase concludes later this quarter.

Why are metallurgical results showing 68% concentrate purity seen as a turning point for U.S. antimony independence?

Locksley’s metallurgical breakthrough has become a central talking point among resource investors following confirmation that its second-stage flotation tests produced a 68.1 percent antimony concentrate—representing 95 percent of the theoretical stibnite maximum of 71.68 percent. Conducted by Independent Metallurgical Operations, a subsidiary of SGS Australia, the tests demonstrated not only exceptional grade but also an efficient flowsheet requiring minimal modification to achieve high recovery rates.

The cleaner flotation process achieved antimony recoveries of 60.5 percent in initial stages, while rougher flotation reached 81.9 percent. When tails are recycled through regrinding and re-flotation, overall recoveries are expected to exceed 80 percent. This level of purity substantially exceeds the marketable benchmark of 55 percent Sb and places the Mojave concentrate among the highest-quality outputs recorded in recent antimony testwork globally. Metallurgical specialists noted that the concentrate’s low impurity profile makes it ideal for conversion into antimony ingot, oxide, and trisulphide—the three forms most in demand by defence contractors and semiconductor manufacturers.

Locksley is now preparing to collect a larger underground bulk sample from DAM to expand testwork across gravity separation, ore sorting, and pilot-scale ingot production. Parallel experiments are planned with Rice University using Deep Eutectic Solvent extraction under the DeepSolv methodology, a low-impact refining process that could yield high-purity metal with minimal environmental footprint.

Institutional sentiment toward the metallurgical results has been broadly positive. Market analysts see the 68 percent concentrate as a technical validation that could accelerate Locksley’s access to government funding mechanisms supporting domestic critical-mineral processing capacity. With the United States currently reliant on imports—primarily from China and Russia—for all of its antimony supply, even modest domestic output could command premium pricing within Department of Defense procurement channels.

What role do Lidar surveys and underground mapping play in fast-tracking Locksley’s Mojave development timeline?

Operational progress at Mojave has kept pace with its laboratory achievements. The Bureau of Land Management has approved Locksley’s expanded Plan of Operations for drilling at the Desert Antimony Mine, contingent only on final bond acceptance. The company has already secured a drilling contractor and intends to commence its first holes in the fourth quarter of 2025.

Ahead of drilling, Locksley completed a detailed LiDAR survey of the underground adits and stopes, generating a high-resolution three-dimensional model of the historic mine workings. The survey, carried out using advanced Elios and DJI drone platforms equipped with precision LiDAR payloads, has provided data critical for both drill targeting and future mine design. Engineers have integrated underground and surface scans to produce a geospatially accurate 3D wireframe that highlights unmined extensions of stibnite mineralisation along strike from the historic stopes.

In tandem, an underground sampling program is being prepared to validate historical production grades and confirm the geometry of quartz-carbonate veins observed in the old workings. Evidence of sheeted, semi-massive stibnite veining has been mapped dipping steeply to the west and northwest, consistent with the orientation of previously mined stopes from the 1930s era. Once sampling results are compiled, Locksley plans to incorporate them into its geological model to guide resource definition drilling and refine mine planning scenarios.

Fieldwork across Mojave’s broader 40-square-kilometre claim package is also intensifying. Regional reconnaissance, stream-sediment analysis, and geophysical survey design are under review, with airborne magnetics and induced polarisation seen as likely techniques to detect additional rare-earth and base-metal anomalies. These simultaneous workstreams underline Locksley’s ambition to transition Mojave from a promising exploration project into a development-ready asset supporting both antimony and rare-earth supply chains.

How does the Mojave Project’s proximity to MP Materials’ Mountain Pass Mine strengthen its rare earth positioning?

Mojave’s geological setting provides Locksley with a strategic edge unmatched by most junior explorers. The project lies immediately adjacent to MP Materials’ Mountain Pass Mine—the only operating rare earth facility in the United States and a key supplier to U.S. magnet and battery manufacturers. Locksley’s 491 claims are divided between the North Block and El Campo Prospect, both of which share structural and lithological continuity with Mountain Pass.

Geologists regard this proximity as more than coincidental. Mojave’s lamprophyre dykes and syenogranite intrusives suggest a deep-seated magmatic system similar to that which produced the carbonatite-hosted bastnäsite mineralisation at Mountain Pass. If confirmed through drilling, this could position Locksley as one of the few explorers with parallel exposure to both rare earth and antimony mineral systems within the same geotectonic corridor.

For the United States, the implications extend beyond geology. Policymakers are increasingly focused on building vertically integrated supply chains spanning critical metals, processing, and manufacturing. Locksley’s dual-commodity profile dovetails with this agenda, enabling it to target multiple federal funding avenues—from the Department of Energy’s Critical Materials Innovation Program to defense-linked supply initiatives. Analysts view this intersection of geology and geopolitics as a powerful tailwind for future valuation growth once Mojave’s maiden resource is established.

What do institutional investors and analysts expect from Locksley Resources’ next exploration and funding milestones?

Investor sentiment toward Locksley has strengthened noticeably since its October announcements. The company’s shares on the ASX have shown improved liquidity and upward momentum, buoyed by optimism that Mojave could become a cornerstone U.S. antimony and rare earth supplier. Retail participation remains active, while institutional investors are beginning to monitor the stock as a potential entry point into America’s reshoring narrative for critical minerals.

Analysts expect the coming quarters to provide multiple catalysts: final bond approval from the Bureau of Land Management, commencement of drilling at DAM and El Campo, and publication of preliminary metallurgical pilot results. A successful drilling campaign confirming grade continuity could pave the way for the company’s first JORC Exploration Target and possibly an inferred resource estimate in 2026.

Experts covering the critical minerals sector also emphasize timing. With geopolitical risk and supply chain diversification dominating Washington’s agenda, assets like Mojave—situated on U.S. soil and already showing proof of high-grade feedstock—could attract strategic partners or government-backed financing under the Defense Production Act. Some market watchers believe Locksley’s expanding North American footprint could make it an attractive target for joint ventures with downstream processors or larger mining groups seeking U.S. exposure.

While enthusiasm is high, investors are aware that execution risk remains. Converting exceptional exploration and testwork results into commercial scale will require capital discipline and sustained technical performance. Nevertheless, the company’s track record of rapid progress since mid-2025 has built confidence that its “mine-to-market” strategy is achievable within an accelerated timeframe.

Can Locksley translate exploration momentum into a domestic supply advantage?

The coming year will test whether Locksley can convert technical success into commercial traction. The company plans to undertake underground bulk sampling at DAM, refine its flotation and gravity separation circuits, and produce pilot-scale antimony metal for downstream testing. Parallel exploration across the broader Mojave corridor aims to delineate additional antimony and rare earth zones that could underpin a multi-deposit development model.

Industry analysts describe Mojave as one of the most strategically aligned junior projects in the U.S. critical minerals landscape—combining high-grade potential, logistical accessibility, and proximity to existing processing infrastructure. Should Locksley achieve consistent metallurgical recoveries and validate grade continuity through drilling, it could become a cornerstone supplier in America’s re-industrialisation push for energy and defence materials.

Investor expectations are therefore centered on execution. The market will be watching how efficiently the company progresses from exploration to feasibility and how it leverages potential partnerships for funding and processing. For now, the narrative remains compelling: a Perth-based explorer building America’s next antimony and rare earth hub in the Mojave Desert—right where history, geology, and policy align.