Gold and silver

Underground operation

Caylloma, Arequipa

4,800 masl

Started in 2016

Tambomayo (100% BVN) is an underground, high-grade gold and silver operation located in the District of Tapay, Province of Caylloma, Region of Arequipa, at 4,800 masl. It successfully produced its first doré bar in December 2016. This mine was discovered by Buenaventura.

Geology: Tambomayo is an epithermal/mesothermal polymetallic deposit in veins of gold and silver, with base metals in veins of quartz, emplaced in andesitic volcanic rocks from the Tertiary. Gold is found in native state and electrum, while silver is found in sulfides and sulfosalts accompanied by galena and sphalerite. It has two main systems of veins: Mirtha, running NW-SE, and Paola, running N-NE. There are also nearby exploration areas.

Mining: The main veins in the deposit form part of the Mirtha and Paola systems. The mineral is extracted via ramps and the 4840 cross-cut using 30-ton trucks. Exploitation methods used include overhand cut and fill and mechanized bench and fill, using low-profile equipment. For the ventilation of works, there are two main 300,000 cfm fans and secondary fans for explorations and developments. For mine drainage, there is a water pumping station with a capacity of 60 l/s, which evacuates water to the 4740 level for treatment.

Metallurgy: The metallurgical process at Tambomayo consists of primary crushing, fine milling, and cyanidation in tanks to obtain rich solutions in gold and silver to be processed using the Merrill-Crowe plant. The precipitate is dried and smelted, obtaining doré bars (gold and silver). The cyanidation tailings enter the flotation process, from where lead-silver and zinc-silver concentrates are obtained.

Treatment Capacity: 2,000 MTD