The Grasberg mine is the largest gold mine and the second largest copper mine in the world. It is located in the province of Papua in Indonesia near Puncak Jaya, the highest mountain in Papua. It has 19,500 employees. It is mostly owned by Freeport-McMoRan (FCX).
FCX operates under a Contract of Work (CoW) agreement with the government of Indonesia, which allows Freeport to conduct exploration, mining and production activities in a 11,100-hectare (27,400-acre) area (Block A). It also conducts exploration activities in a 167,000 ha (413,000 acres) area (Block B).
All of Freeport's proven and probable mineral reserves and current mining operations are located in Block A. The mine has three mining operations: the open pit, the Deep Ore Zone underground mine, and the Big Gossan underground mine. A fourth, the Deep Mill Level Zone, is being developed.
According to en.wikipedia