Name: Uchucchacua mine.

Location: The mine is located in Oyón, Lima, Peru.

Controlling Company: Buenaventura.

Brief Description: The mine comprises the Socorro, Carmen, and Huantajalla mines, whose production is extracted through the Luz and Master shafts.

Brief History: Uchucchacua was discovered by Buenaventura and started operation in 1975.

Products: Silver, lead and zinc.

Geology/Mineralisation: Uchucchacua is a silver-bearing deposit with base metals and a high content of manganese hosted in the carbonate rock of the Jumasha Formation from the Upper Cretaceous, related to intrusives from the Miocene. It comprises veins and replacement bodies associated with systems of north-east to south-west, east to west, and north-west to south-east structures. Of particular importance are the Uchucchacua, Socorro-Cachipampa, Rosa and Sandra faults. Mineralogy is varied and complex, with the occurrence of silver in sulphides and sulphosalts, with abundant alabandite and manganese calcium silicates. Lead and zinc increase in proximity to the intrusives. Work is being done in the Socorro, Carmen-Casualidad, and Huantajalla Mines.

Reserves: Total proven and probable reserves as at December 31, 2017, were estimated at 4.89-million tonnes grading 2.18% zinc.

Mining Method: Overhand cut-and-fill and bench-and-fill methods are used, both mechanised, using low-profile equipment.

Major Infrastructure and Equipment: The metallurgical process at Uchucchacua comprises two circuits.

Circuit 1 has a capacity of 2 810 t/d and includes primary crushing, milling, and ore flotation, obtaining lead/silver, zinc/silver and pyrite concentrates.

Circuit 2 has a capacity of 1 100 t/d and includes primary crushing, milling and ore flotation, obtaining lead/silver, zinc/silver and pyrite concentrates.

The pyrite concentrates from both circuits are sent to a 300 t/d cyanidation plant. The cyanidation process is performed in tanks and thickeners. The solution obtained is treated using the Merrill-Crowe process, and the precipitate obtained is dried and smelted to obtain high-purity silver bars.

The concentrates with a high manganese content produced at Uchucchacua are treated at the Río Seco leaching plant for subsequent sale.

Prospects: The Uchucchacua mine is undergoing a debottlenecking process, which includes the mines hoist and ventilation systems.

Contact: Buenaventura corporate communications Diego Uceda Noguerol.

Contact Details:
Tel  +511 419 2500
Email comunicacion.corporativa@buenaventura.pe
Website http://www.buenaventura.com