Ev Resources Ltd has completed preliminary metallurgical testwork on material from the Vinatas antimony operation in Mexico, achieving a cumulative antimony recovery of up to 78.6% using conventional flotation. The work identifies a second regional ore source capable of feeding the company’s Tecomatlán processing facility.

The test program, supervised by engineer Armando G. Aguilar at independent laboratory Metalurgia y Equipos, evaluated bulk flotation, controlled grinding, gravity cleaning and centrifugal concentration. Initial bulk flotation on material grading 13.8% antimony achieved a cumulative recovery of 78.6% and produced a concentrate grading 58.8% antimony using potassium amyl xanthate and lead nitrate. A follow-up test achieved 75.8% recovery under similar grinding and reagent conditions.

Upgrading the second test's bulk flotation concentrate on a Wilfley shaking table produced a stibnite concentrate grading 68.3% antimony with 4.36% silicon dioxide. Subsequent processing of the flotation tailings through three sequential passes using a Falcon centrifugal concentrator reduced the final tailings grade from 6.14% to 2.17% antimony, demonstrating potential to limit metal losses.

The preferred preliminary flowsheet incorporates grinding to approximately 87% passing 200 mesh, conventional bulk flotation, gravity cleaning of concentrates, and centrifugal recovery on tailings. This circuit aligns with the installed gravity and flotation configuration at the Tecomatlán processing plant, which is targeted for completion and operation within a 10-to-12-month timeline.

“Vinatas is now the second regional third-party feed source, alongside Chinantla, to demonstrate strong metallurgical performance using conventional processing technologies compatible with Tecomatlán.” 

— Miguel Barahona, Interim CEO

The metallurgical results compare favorably with previous testwork on the Chinantla feedstock, which achieved an 81.1% antimony recovery and a 42.4% concentrate grade. While Chinantla previously advanced to a binding five-year ore supply agreement in August 2026, Vinatas is currently covered by a memorandum of understanding signed in May 2026. EV Resources intends to evaluate progressing discussions toward a binding ore supply agreement for approximately 80 tonnes per month of mineralised material or direct-shipping ore.

The technical evaluation coincides with broader regional work by the company, which recently established a maiden exploration target of 1.8 to 5.0 million tonnes containing 70 to 166 kilotonnes of antimony metal at its Los Lirios project, further advancing its regional supply strategy.

Read the full announcement: Vinatas Delivers 78.6% Sb Recovery and 68.3% Sb Concentrate