Peruvian miner Minsur S.A., controlled by local holding Breca Group, engages in the exploration and mining of mineral deposits, mainly gold and tin. It operates the San Rafael mine, in the Puno department, and the Pucamarca mining unit, in the Palca district, as well as a smelter and refinery plant, in Pisco. The San Rafael mine is focused on tin production and processes 2,900 metric tonnes per day (MTPD) of casseterite, while the Pucamarca open-pit mine processes 21,000MTPD of gold ore, sold exclusively to the United States. Minsur's Pisco plant produces high quality refined tin, which are mostly distributed by sea to Europe, United States, Canada, Asia, Middle East and Latin America. Minsur is the majority shareholder of Minera Latinoamericana S.A.C., which in turn is the main shareholder of Mineração Taboca S.A., a company that operates the Pitinga mine, in the Brazilian state of Amazonas, which produces tin, niobium and tantalum, and also owns the Pirapora smelter, in São Paulo. Through the subsidiary Cumbres Andinas S.A., Minsur owns a 70% interest in Marcobre S.A.C., a mining company that develops the Mina Justa copper ore project, located in the region of Ica, Peru. Minsur was founded in 1977, after the Breca Group acquired the Peruvian subsidiary of Minsur Partnership Limited de Bahamas. The company is headquartered in Lima, Peru.