The Porgera mine is located in the Papua New Guinea highlands, 130 kilometres west of the town of Mount Hagen. The development of the mine has been carried out in a series of stages, starting production in 1990 and progressively expanding and upgrading mining operations and processing facilities. The mine has a 6Mt/a concentrator with a crushing, grinding, flotation, autoclave and pressure oxidation circuit. Gold is recovered by cyanide leaching, with average annual production in excess of 500koz. The mine is operated by the Porgera Joint Venture (Barrick 47.5% and Zijin 47.5%).