How Did Nova Minerals Achieve a 132% Antimony Grade Upgrade in Alaska?

Ore Sorting Breakthrough at Estelle

Nova Minerals Limited has reported a significant milestone in its Estelle Project in Alaska, with ore sorting test work on a 500kg bulk sample from the Styx prospect delivering a 132% upgrade in antimony grade. The single-pass ore sorting produced a concentrate grading 49.1% antimony trisulfide (Sb2S3), more than doubling the feed grade of 24.5% Sb2S3, while recovering 60.3% of the contained antimony in just 26.1% of the mass.

This result not only confirms the amenability of Estelle’s antimony ore to sensor-based ore sorting technology but also highlights the potential for low-cost, scalable onsite processing. The ability to produce a high-grade concentrate early in the value chain is a critical step toward establishing a domestic U.S. supply of this strategic mineral.

Synergies Between Antimony and Gold

Interestingly, the test work also revealed that gold is preferentially rejected to the tailings during ore sorting, with gold recovery of 52.5% and an upgraded grade from 1.90 g/t to 2.99 g/t in the tailings stream. This separation opens the door to integrated processing circuits that could simultaneously optimize recovery of both antimony and gold, enhancing the overall project economics.

Nova’s CEO Christopher Gerteisen emphasized the strategic importance of these findings, noting that the Estelle Project is well-positioned to become the first fully integrated U.S. domestic antimony producer at scale. The synergy between gold and antimony circuits further strengthens the project’s value proposition.

Strategic Context and Next Steps

With global supply chains for critical minerals under increasing strain, particularly due to export restrictions from China, Nova’s Estelle Project emerges as a timely and strategic asset. Antimony is essential in defense applications, electronics, and munitions, making a secure domestic supply a priority for Western governments.

Nova is actively engaging with U.S. government bodies, including membership in the Defense Industrial Base Consortium and applications for Department of Defense grants, to fast-track exploration and infrastructure development. The company has outlined a conceptual flowsheet featuring onsite ore sorting to produce direct shipping ore, enabling early cash flow generation while downstream processing facilities are developed.

Further beneficiation and purification test work is underway to refine the processing flowsheet, and ore sorting results from the Stibium prospect are expected soon. These developments will be critical in confirming the project’s near-term production potential and cost profile.

Implications for Investors and Market

Nova Minerals’ latest metallurgical results mark a pivotal advancement in the Estelle Project’s development. The demonstrated ability to upgrade ore grade significantly and recover a majority of antimony in a low-mass concentrate suggests a pathway to efficient, low-capital processing. Combined with strategic government engagement, this positions Nova as a potential leader in re-establishing U.S. antimony production, a market currently dominated by imports.

Investors should watch closely for upcoming test results, further engineering studies, and regulatory progress that will clarify the timeline and scale of production. The evolving geopolitical landscape and critical mineral demand dynamics add further weight to Estelle’s strategic value.