The potential for low-cost gold production at Flagship Minerals’ Pantanillo gold project in Chile has been significantly bolstered by promising metallurgical results. Located in the renowned Maricunga gold belt, the project has demonstrated rapid gold recoveries exceeding 80 percent in oxide material, positioning it for a viable heap leach operation.
Recent analyses of historical drill holes indicated a gold recovery rate of 79.8 percent in bottle roll tests from oxide material. Additionally, column leach tests produced an impressive 80 percent recovery, suggesting that the project could feasibly support a cost-effective heap leach mining strategy. The Pantanillo gold project is estimated to contain 47.4 million tonnes at 0.69 grams per tonne (g/t) gold, translating to approximately 1.05 million ounces, predominantly located in oxide material, ideal for heap leaching.
Flagship Minerals is considering implementing dump leaching techniques to further reduce costs by eliminating the need for crushing, screening, and rehandling materials. This is particularly relevant given the success of Rio2 Limited’s Fenix Gold Project located 40 kilometres north, which achieved a 75 percent recovery via similar techniques at 0.48 g/t gold and an all-in sustaining cost of just US$1,237 per ounce.
According to Paul Lock, managing director of Flagship Minerals, the leaching test results reinforce Pantanillo’s potential as a large and scalable heap leach opportunity. The company is advancing with confirmatory test work aimed at optimizing particle size, recovery rates, and processing times. Moreover, Flagship plans to utilize a recently acquired dataset of 30,000 meters of drilling data from Anglo American to convert its gold estimate into a JORC-compliant resource.
Infill and extensional drilling campaigns are scheduled for later this year, focusing on enhancing oxide and sulphide resources at the Pantanillo Central, Quebrada Pantanillo, and Oro 52 prospects. Lock emphasized the company’s strategy to delineate sufficient mineral resources to support the development of an open-pit mining operation and heap leach processing, targeting an ambitious production goal of 100,000 ounces of gold annually for over a decade.
The Pantanillo project is situated in a highly favorable region, characterized by substantial gold deposits. The Maricunga belt hosts over 65 million ounces of gold, anchored by the Norte Abierto mine, a joint venture between Newmont and Barrick, located 40 kilometers southwest of Pantanillo. Nearby, Kinross’s 10.7-million-ounce Maricunga project is 25 kilometers to the west, while Hochschild’s 11-million-ounce Volcan deposit lies just 10 kilometers northwest.
The extensive 110-square-kilometer project area features numerous geophysical targets associated with magnetite and pyrite, which are highlighted through magnetic surveys. Recent drilling efforts on priority targets revealed substantial intercepts, including 116 meters at 1.5 g/t gold and 493 meters at 0.53 g/t from a depth of 9 meters. These results underscore Pantanillo’s potential for bulk-tonnage open-pit mining.
With gold prices surpassing US$5,500 an ounce, Flagship is poised to capitalize on a favorable market environment. The company is leveraging the data obtained from Anglo American, acquired for US$2.85 million, to expedite its development plans while exploring additional targets such as Pantanillo Central and T1 for broader resource expansion. Significant alteration zones to the northwest of the current resource and geophysical anomalies to the southeast signal promising gold potential.
If Flagship Minerals successfully confirms a low-cost heap leach operation for Pantanillo, along with a new one-million-ounce JORC-compliant resource, it could swiftly advance into feasibility studies for a project that promises exceptional economic returns within a thriving gold market.
