Peruvian miner Antamina, which runs one of the largest copper-zinc pits, produced 450,000 metric tons of copper in 2012 and expects similar output in 2013, according to company officials. The mine, jointly owned by BHP Billiton, Xstrata, Teck and Mitsubishi, announced a $1.28 billion expansion plan for facilities and ore processing capacity following a 2009 study increasing reserves 77%, and the mine’s life to 2029 from 2023. Copper and zinc represent 86% of revenues, while molybdenum, silver and lead are also set to increase.