ASX-listed American Tungsten and Antimony (AT4) has successfully completed its acquisition of Nexus Metals and the Del Sol hydrometallurgical refinery, in Nevada, in the US.

In a statement to shareholders, the company says the acquisitions mark a major milestone in AT4's strategy to establish an integrated, US-based critical minerals business, with domestic refining capability supporting its plans for antimony and tungsten production.

"Securing Del Sol is a major milestone for AT4. We now own an established US refinery that has already demonstrated the ability to produce high-purity antimony metal from American-mined material.

“This is a powerful foundation on which to build a domestic critical minerals business. Our focus now shifts to scaling that capability, advancing product qualification and commercial relationships, and progressing the studies required to expand Del Sol into tungsten ammonium paratungstate production.

“With this acquisition complete, we have secured the processing infrastructure at the heart of our mine-to-metal strategy. The opportunity now is to translate that strategic position into sustained operations and commercial outcomes,” says AT4 CEO Casper Adson.

AT4 describes the completion of the Del Sol acquisition as a transformational step in AT4's strategy to establish a vertically integrated US critical minerals business.

With ownership now secured, AT4 says it is now positioned to advance its tungsten and antimony processing and specialty product plans, including the proposed Del Sol Mineral Intelligence Engine, a multi-source feedstock evaluation and qualification capability to characterise third-party feedstocks.

Del Sol provides the critical downstream link between AT4's US mineral interests and its ambition to become a domestic producer of strategically important refined metals.

The company adds that the revised structure has benefits relating to AT4's proposed Nasdaq listing. Acquiring the underlying US assets directly, rather than shares in the existing project companies, is expected to simplify the company's ownership structure and associated US regulatory and financial reporting considerations, including those relating to historical financial information.

The company says the revised structure preserves the underlying commercial terms of the transaction and is intended to support an efficient progression towards the proposed Nasdaq listing.

The US component now comprises two separate asset acquisitions, each of which completes independently. This includes the refinery transaction and the White Spar transaction.

The company explains that the acquisition of the White Spar project interests in Arizona, in the US, remains subject to outstanding conditions, with the associated consideration payable only on completion.

With the acquisition of the Del Sol Refinery complete, AT4 has highlighted near-term priorities.

This includes advancing refinery antimony processing operations and product qualification activities with prospective customers and progressing the proposed expansion of the refinery into higher-value antimony products and tungsten APT processing, including the engineering study being undertaken by Metso.

Other priorities include advancing commercial engagement with prospective US customers, strategic partners and government agencies.

AT4 says it is also continuing to progress the company's proposed Nasdaq listing, subject to applicable regulatory and exchange approvals.

Meanwhile, the company has also confirmed the appointment of Timothy Walker as a nonexecutive director of the company, effective October 30, as the nominee of the vendors.