The Grasberg open-pit mine has been operating since about 1993 and while copper is the main product, it also has the largest gold reserves of any mine in the world. The mine doesn’t have extremely high-grade gold ore, it is just larger than almost any other ore deposit. The town of Tembagapura and the processing facilities were all built for the now exhausted Gunung Bijih Mine, which translates as “Ore Mountain”. Mining at Gunung Bijih started in 1974 and, while it was much smaller than Grasberg, it had very high grades and was worth the trouble of working in a very remote place.
The bottom of the open-pit is currently at about 3,200 meters above sea-level. (The highest level of the Big Gossan underground mine nearby is at 3,120 meters!) This is getting too deep to profitably mine as an open pit mine and the pit is planned for closure in 2015. A new underground mine called the Grasberg Block Cave Mine is currently being built 500 meters below the pit. Once built the Grasberg Block Cave Mine will be the largest underground mine in the world.
One of the most exciting sights from the Grasberg Mine is Puncak Jaya (Victory Peak) which is a little over 16,000 feet tall and the highest point between the Himalayas and the Andes. (Thanks Wikipedia.) There are also three small glaciers nearby.
Our tour guide was Ichal from the Surface Geology department. He is originally from Fak-Fak, just north of Australia, and has been working here for four years.
