Ore Hardness and Water Use: Key Challenges Ahead for Tesoro Gold’s Ternera Project

Metallurgical Breakthrough at Ternera

Tesoro Gold Limited has announced a significant advancement in the processing potential of its Ternera Gold Deposit, part of the El Zorro Gold Project in Chile. Recent metallurgical testwork has confirmed that the ore can achieve gold recoveries exceeding 95% using a straightforward and cost-effective Cyanide In Pulp (CIP) method. This outcome not only validates earlier test results but also highlights the deposit’s amenability to conventional processing techniques.

Sustainability and Efficiency in Focus

One of the standout features of the testwork is the use of brine wastewater sourced from the nearby Aguascap Totoralillo desalination plant. This approach underscores Tesoro’s commitment to sustainable water management in a region where water resources are often constrained. Moreover, the process demonstrated very low reagent consumption, with cyanide usage below 0.2 kilograms per tonne and lime at around 8 kilograms per tonne, suggesting operational cost efficiencies and environmental benefits.

Ore Characteristics and Processing Implications

The Ternera ore exhibits favorable physical properties, including consistent hardness and grindability, with a Bond Work Index averaging 20.9 kWh/t. While the ore is classified as hard to very hard, it fractures easily during crushing, which bodes well for comminution. Gravity recoverable gold accounts for approximately 41% of the total recovery, consistent across all grade ranges, indicating a robust and predictable metallurgical response.

Strategic Impact and Next Steps

These metallurgical results are a critical milestone for Tesoro Gold as they provide a solid technical foundation for the design of the processing plant and feed directly into the forthcoming pre-feasibility study. Managing Director Zeff Reeves expressed confidence in the robustness of the current flowsheet and highlighted the importance of these findings in advancing the project towards development. The company plans to commence pre-feasibility studies in the coming months, which will further refine economic and operational parameters.

Broader Context

Located in Chile’s Coastal Cordillera, the El Zorro project benefits from established infrastructure and a skilled mining workforce. Tesoro’s 95% owned subsidiary controls over 95% of the project concessions, positioning the company well to capitalize on this discovery. The deposit’s consistent metallurgical performance, absence of deleterious elements, and straightforward processing route enhance its attractiveness amid a competitive gold mining landscape.