American Tungsten & Antimony has produced one antimony ingot assaying 99.8% from US-mined material, meeting the highest ASTM B237 grade and exceeding the Regulus II specification. The result comes as the company pursues US government funding and offtake arrangements, although no commitments have been secured and AT4 does not yet control the relevant assets.
- One of five ingot samples assayed at 99.8% antimony
- Sample met ASTM B237 Grade A and exceeded Regulus II
- Four other samples returned between 99.5% and 99.6% antimony
- White House roundtables and congressional site visits focused on funding and offtake
- Del Sol refinery and White Spar mine acquisition remains incomplete
One sample reaches highest ASTM antimony grade
American Tungsten & Antimony Ltd (ASX:AT4; OTCQB: ATALF) has produced an antimony ingot grading 99.8% from material mined in Arizona and refined in Nevada. The result meets ASTM B237 Grade A, the highest grade under that specification, and exceeds the 99.65% threshold for Regulus II antimony.
But the headline number needs a careful reading. NSL Analytical Services tested drill shavings from five ingots: one returned 99.8%, while the other four assayed between 99.5% and 99.6%. AT4 said the strongest sample was produced after optimised electrowinning conditions followed by fire refining, which it expects to consistently produce ingot above Regulus II grade. The announcement does not report production volumes, recovery rates or broader campaign output.
US mine-to-metal route moves towards customer testing
The assay gives the company a more commercially useful result than its earlier physical demonstration, which had converted White Spar material into antimony ingot without disclosing product quality. AT4 now says the first US mine-to-metal test has produced a sample that can be measured against both a commercial grade and an industry specification.
That distinction matters for a company pursuing a domestic supply chain for a mineral used in ammunition, primers and other defence applications. AT4 says the demonstrated production capability enables direct discussions with the US Defense Logistics Agency, Project Vault and defence primes. Those conversations remain discussions rather than customer qualification, sales or binding offtake agreements.
White House meetings target funding and offtake
AT4 Executive Director of Government Relations and Marketing Andre Booyzen joined a World Trade Center Utah delegation at White House critical minerals roundtables on 5 October. The company said the meetings focused on pursuing further US government funding and offtake arrangements, with participants including the US Trade Representative, the National Security Council and the Office of Strategic Capital.
Members of Congress then visited the White Spar mine in Arizona and Del Sol refinery in Nevada. Congressman Paul Gosar, House Natural Resources Committee chairman Bruce Westerman and Congressman Eli Crane were cited as supporting AT4’s strategy. The visits do not represent US government endorsement, funding, offtake or any other commercial commitment.
Asset ownership remains the immediate constraint
The most important qualification sits outside the assay table: AT4’s acquisition of Nexus Metals, which holds rights relating to Del Sol and White Spar, has not completed. The company says it does not currently own or control either asset. Nor does one Grade A sample establish that future production will consistently meet ASTM B237 Grade A, Grade B or Regulus II specifications.
The next evidence will need to come from repeat ingots made under the optimised process, alongside production rates, recoveries, customer qualification and a completed acquisition. Until then, Washington access and a strong laboratory result improve the proposition, but they do not yet turn it into a contracted supply chain.
Bottom Line?
The 99.8% result strengthens AT4’s technical case, but repeat production, asset control and binding government or customer agreements remain unresolved.
Questions in the middle?
- Can the optimised electrowinning and fire-refining conditions consistently produce Regulus II or ASTM Grade A ingot?
- Will AT4 secure binding US government funding or offtake arrangements from its current discussions?
- When will the Nexus Metals acquisition complete, giving AT4 control of the White Spar and Del Sol assets?