American Tungsten & Antimony Ltd has engaged Metso Finland Oy to complete a Scoping Study at the FEL1 Concept Study level for an ammonium paratungstate production circuit at the Del Sol Refinery in Amargosa Valley, Nevada.

The study will evaluate an ammonium paratungstate circuit within the existing permitted facility as an alternative to building a standalone greenfield processing plant, using the asset's existing hydrometallurgical infrastructure and utilities.

The Del Sol Refinery is an existing alkaline leach and electrowinning hydrometallurgical facility located on approximately 40 acres of privately owned land in Nevada, which the company agreed to acquire in July 2026. The acquisition remains subject to conditions precedent.

The processing strategy for the facility incorporates feed sourced from the company's Dutch Mountain tungsten project in Utah under a hub-and-spoke operating model.

The study will be sized to a proposed Phase 1 design capacity of 2,500 tonnes per annum of ammonium paratungstate and will propose a pathway to a potential future Phase 2 modular expansion to 5,000 tonnes per annum. Deliverables include a preferred conceptual flowsheet, preliminary mass balance, main equipment list, an AACE Class 5 capital cost estimate, an indicative operating cost estimate, permitting commentary, and a roadmap to an FEL2 prefeasibility study.

The current study will provide the technical basis required to support future applications under United States federal critical minerals funding programs.

“Del Sol is a constructed and permitted hydrometallurgical plant on American soil. Putting an APT circuit inside an existing footprint rather than building on a greenfield site has the potential to materially reduce the capital required and the timeline to commence producing a domestic tungsten product.” — Casper Adson, Chief Executive Officer

“Metso, a recognised international supplier of process technology, equipment and services to the minerals processing and metals refining industries, will apply its extensive expertise to the assessment of a tungsten APT circuit at Del Sol. The resulting flowsheet, capital and operating cost estimates will be prepared to a standard suitable for review by government, offtake counterparties and prospective funding partners.” — Timothy Morrison, Executive Chairman

American Tungsten & Antimony awaits the satisfaction or waiver of conditions precedent to complete the acquisition of the Del Sol Refinery and White Spar Antimony Mine while Metso advances the concept study and prepares the cost estimates.

Read the full announcement: Tungsten APT Refinery Expansion to Commence