Argentina | Casposo - Manantiales Mine Complex
- Location: San Juan, Argentina.
- Metals: Care & Maintenance.
- Ownership: 100%.
- Status: Care & Maintenance.
- Deposit Type: Low Sulphidation Epithermal Deposit.
- Infrastructure: A crushing plant and a 1,100 tpd mill, a dry-stack tailings management facility and waste rock dumps, low-grade ore, run-of-mine stockpiles, administrative building, cafeteria, laboratory, maintenance facilities, core processing, and sample preparation facility.
The Cordillera Principal runs along the Chile-Argentine border for approximately 1,500 km. It is a volcanically and seismically active zone formed by the subduction of the Nazca plate beneath the South American continent.
The main basement is formed by Permian–Triassic intrusive and volcanic rocks of calc-alkaline affinity and andesitic to rhyolite composition, regionally known as the Choiyoi Group. These younger sediments of Jurassic and Cretaceous age have been thickened by compression and thrusting since the Late Cretaceous in a thin-skinned fold thrust belt.
The Mine is located on the eastern border of the Cordillera Frontal. In the Mine area, the Cordillera Frontal is underlain by marine metasediments of the La Puerta Formation. These sedimentary sequences are overlain by a thick intrusive and volcanic sequence assigned to the Permian Triassic Choiyoi Group. The main host rocks at the property are basal andesitic volcanic flows, tuffs, and breccias overlain by rhyolite, rhyolite-dacite flows, and dacitic ignimbrite flows.
The Casposo gold–silver mineralization occurs in the rhyolite and underlying andesite, which is associated with banded quartz–chalcedony veins, typical of low sulphidation epithermal environments.
Mineralization occurs along a 10km long west–northwest to east-southeast trending regional structural corridor. The primary Kamila Vein system forms a sigmoidal set 500m long near the center. The Mercado Vein system is the northwest continuation of Kamila and is separated by an east–west fault from the Kamila deposit. The Julieta Zone is located five kilometers along strike to the northwest of the Kamila and Mercado deposits and is situated within the same regional structural corridor. The Casposo Norte deposit is located on a parallel structure approximately two kilometers north of Kamila.
Community and Environment
The Casposo/Manantiales Mine Complex is located next to Calingasta, a mining town and home to a Mining Technology school. Therefore, the mine counts on better-than-average local support.
Its Environmental Impact Assessment (EIA) was submitted in 2007, reviewed by a multi-disciplinary commission, and approved in 2009. Casposo received the ISO 14001 certification for its Environmental Management Plan in 2012.