Name: Coimolache mine.

Location: The mine is located in the districts of Hualgayoc and Chugur, in Hualgayoc, Cajamarca, Peru.

Controlling Company: Compañía Minera Coimolache, in which Buenaventura owns a 40.1% share.

Brief Description: Coimolache is an openpit gold operation. Mining is conducted in the Tantahuatay 2 and Ciénaga Norte pits.

All production at Coimolache is turned into gold and silver doré, which are later sold.

Brief History: Operations at Coimolache started in 2011.

Products: Gold and silver.

Geology/Mineralisation: Coimolache is a high-sulphidation epithermal deposit, with outcropping gold and silver mineralisation in oxides, connected to silicified breccia associated with a pervasive siliceous alteration.

Below the oxides level, there is mineralisation comprising predominantly arsenical copper and, to a lesser extent, covellite and supergene chalcocite. This epithermal event overprints a skarn, with retrograde alteration identified at depth, with clean copper mineralisation.

Reserves: Total proven and probable reserves as at December 31, 2017, were estimated at 68.1-million tonnes grading 0.012 oz/TMS gold and 0.23 oz/TMS silver.

Mining Method: Openpit.

Major Infrastructure and Equipment: Run-of-mine ore, obtained from blasting in the openpit, is leached using cyanide solution. Two processes are conducted in the plant: Merrill-Crowe (zinc precipitation), and adsorption, desorption and regeneration using activated carbon.

Prospects: Coimolache signed a contract with Cerro Corona (Gold Fields) to buy oxide material in February 2018. Based on this agreement, the mine will buy 6.6-million tonnes of ore over three years.

Contact: Buenaventura corporate communications Diego Uceda Noguerol.

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