EV Resources Pivots to Flotation Strategy at Tecomatlán Plant after Strong Test Results

EV Resources (ASX: EVR) has confirmed that metallurgical test work on ore from Mexico’s Chinantla antimony project using a flotation-led flowsheet could potentially triple the amount of antimony recovered at the refurbished Tecomatlán plant compared to gravity concentration alone.

The test work, which used Chinantla ore as a regional, third-party feedstock source under a non-binding memorandum of understanding, demonstrated an 81.1% antimony recovery rate to produce a flotation concentrate grading 42.4%.

Chinantla ore is expected to cover at least 50% of Tecomatlán’s nameplate capacity and is seen as highly amenable to conventional sulphide flotation.

Demonstrated capability to produce an antimony concentrate graded more than 60%, which is considered “comfortably higher” than typical smelter specifications.

Comparative Flotation Tests

The flotation route returned the highest recovery and best concentrate grades when directly tested against gravity concentration alone (which recovered 29.25% antimony) and gravity concentration followed by flotation of the gravity tailings (74.04%).

Additional tests are advancing to confirm a complete traditional flotation flow sheet, which is expected to further increase the potential concentrate grades of third-party feedstock.

EV Resources is now pivoting from an earlier two-phase gravity-flotation development timeline for the Tecomatlán plant to a direct integrated flotation upgrade path using the existing flotation circuit with additional high-efficiency tank cells installed to capture performance improvements.

Insertion of new cells and commissioning and integration of the flotation circuit will require minimal additional capital expenditure based on the company’s preliminary assessment, and is estimated to be a fraction of the cost of constructing a new gravity and flotation plant.

Environmental Permitting

The revised strategy could potentially compress the overall production pathway timeline to less than 12 months and deliver a materially improved outcome via the flotation route.

EV Resources has been advised that the current permitting pathway for operation of a flotation circuit takes approximately seven months.

The process would run concurrently with plant refurbishment activities.

The company has commenced preparation of a preventive environmental report prior to lodging an environmental statement as pre-requisites for flotation circuit operation at Tecomatlán.

Technical Strategy Milestone

EV Resources managing director Mike Brown said the comparative tests had been a technical milestone for the Tecomatlán third-party strategy.

“Achieving around 81% antimony recovery and confirming we can produce a commercial-grade concentrate, with a possible optimisation path to 60% antimony, from third-party ore using conventional, well-understood flotation technology gives us real confidence in our hub-and-spoke model,” he said.

“We expect to be able to execute this plan with minimal additional CAPEX relative to the Phase 1 budget and timeline.”

“Combined with the start of environmental permitting for a flotation circuit, we are methodically de-risking the pathway to processing regional antimony ore at Tecomatlán at a time of acute global antimony supply constraints.”