Casposo Mine Reserves Total 2.15Mt at 1.31 g/t Au, NPV Hits US$72.7M
Austral Gold Limited has released an updated Mineral Resource and Reserve estimate for its Casposo Mine in Argentina, underpinning plans to restart production with strong economic fundamentals. The report highlights a 74-month mine life and a compelling after-tax NPV of US$72.7 million.
- Proven and Probable Reserves – 2.149 million tonnes grading 1.31 g/t Au and 58.52 g/t Ag
- Measured and Indicated Resources, 2.258 million tonnes at 1.48 g/t Au and 59.91 g/t Ag
- Projected mine life of 74 months with average annual production of 11,495 oz Au and 468,434 oz Ag
- After-tax NPV of US$72.7 million at 11.8% discount rate and all-in sustaining cost of US$1,695/oz Au
- Contract mining strategy and completed plant refurbishment support operational restart
Updated Reserves Signal Production Restart
Austral Gold Limited (ASX, AGD) has announced a comprehensive update to the Mineral Resource and Mineral Reserve estimates for its 100% owned Casposo Mine in Argentina. This update reinforces the company's strategy to resume production at a site with a proven track record of gold and silver extraction.
The updated Proven and Probable Mineral Reserves stand at 2.149 million tonnes grading 1.31 grams per tonne (g/t) gold and 58.52 g/t silver, translating to recoverable ounces of approximately 80,000 ounces of gold and 3.276 million ounces of silver. Complementing this, Measured and Indicated Mineral Resources total 2.258 million tonnes at 1.48 g/t gold and 59.91 g/t silver, with additional inferred resources offering upside potential.
Economic Viability and Mine Life
The Casposo Mine is projected to operate for 74 months, with an estimated annual average production of 11,495 ounces of gold and 468,434 ounces of silver. The economic analysis reveals an after-tax net present value (NPV) of US$72.7 million, discounted at 11.8%, and undiscounted pre-tax free cash flows of US$137.9 million. The all-in sustaining cost (AISC) is estimated at US$1,695 per ounce of gold, reflecting a competitive cost structure.
Austral Gold plans to leverage contract mining services to optimize capital expenditure, focusing sustaining capital investments on reprocessing mineralized material from the Dry Stack Tailings Dam (DCS). The processing plant refurbishment, supported by a US$7 million investment, is nearing completion with commissioning expected in the third quarter of 2025.
Technical and Environmental Foundations
The reserve update is underpinned by rigorous geological modeling, extensive drilling, and robust quality assurance and control protocols. The Casposo geology team has applied industry-standard methodologies, including a 25-meter drill grid pattern to classify Indicated Resources, consistent with global best practices for low-sulfidation epithermal deposits.
Environmental compliance remains a priority, with all necessary permits in place and an active Environmental Impact Assessment (EIA) process. The mine maintains strong community relations, particularly with the nearby town of Calingasta, and follows internationally recognized standards for mine closure and rehabilitation.
Looking Ahead, Exploration and Growth Opportunities
Austral Gold highlights the potential for resource growth through infill drilling and exploration in areas such as Manantiales, B-Vein, Casposo Norte, and Cerro Amarillo. The company also plans to evaluate underground mining potential to extend the mine life beyond the current open-pit focus.
With gold and silver prices remaining robust, the Casposo Mine is well positioned to deliver value to shareholders as operations restart. The company’s strategic use of contract mining and ongoing plant optimization efforts aim to enhance operational efficiency and cost control.
Bottom Line?
Austral Gold’s updated Casposo reserves set the stage for a production restart backed by solid economics, but the path ahead hinges on successful exploration and operational execution.
Questions in the middle?
- How will infill drilling impact the conversion of inferred resources to reserves, particularly in Manantiales and B-Vein?
- What are the prospects and timelines for evaluating and potentially developing underground mining at Casposo?
- How will fluctuations in gold and silver prices affect the mine’s economic viability and planned production schedule?
