The history of PT Freeport Indonesia (PTFI) began when an exploration manager of Freeport Minerals Company, Forbes Wilson went on an expedition to Papua in 1960. This was after he had read a report about the discovery of Erstberg or the Ore Mountain, a mineral deposit, by a Dutch geologist named Jacques Dozy in 1936.

After the first signing of a contract of work with the Government of Indonesia in April 1967, PTFI started exploration at Ertsberg in December 1967. Large scale construction began in May of 1970, continued by the first copper concentrate export in December of 1972.

After geologists discovered world class reserve Grasberg in 1988, PTFI’s operation became one of the largest copper/gold mining project in the world. At the end

of 1991, the second contract of work was signed and PTFI was extended the right by the Indonesian government to continue its operation for 30 years.
In 2005, PTFI produced and sold concentrate containing 1.7 billion pounds of copper and 3.4 million ounces of gold. Currently, PTFI is also one of the largest taxpayers in Indonesia. Since 1992 till 2005 direct benefit from the company’s operation for Indonesia in the form of dividends, royalties and taxes reached around US$3.9 billion.

During that time PTFI has also provided indirect benefits in the form of wages, salaries and allowances, domestic reinvestment, purchasing goods and services, as well as regional development and donation. Currently, PTFI implements two mining techniques, namely open-pit mining that uses transportation trucks and large electrical shovel at the Grasberg mine, as well as block-caving at the underground mine Deep Ore Zone or DOZ.

The crushed ore is transported to the processing mill thorough a series of conveyor belts and an orepass. A combination of crushing technique is applied, including the utilization of a semi-autogenous grinding (SAG) machine and a ball mill to crush the mine ore to become very fine sand.

Subsequently, this is followed by a floating process utilizing a reagent, an alcohol and lime based substance to separate the concentrate containing the copper, gold and silver ore that will float towards the surface and will then be skimmed off as the end product. The residue of the rocks that do not contain economic value will sink to the bottom as tailing and released through a riverflow towards the sedimentation area in the lowland.

Subsequently the concentrate in the form of slush is distributed from the processing mill towards the dewatering plant at Amamapare harbor through a 110 km long pipeline. The dried concentrate is stored at the Amamapare Port before it is sold to the smelting plants all over the world.

PTFI continued to strive to become a model economic developer in Indonesia processing natural resources and optimizes the social benefits fro the nation, including the Papuan community. The company also endeavors to minimize the impact on the environment and is committed to continuously enhance every aspect of the operation.

Grasberg is mined by utilizing an appropriate open pit technique because of its location close to the surface. By using this technique it is possible to utilize heavy duty equipment for the huge land work involved, enabling the highest mining level at the lowest cost per unit level.

Main faculties at the open pit mine include maintenance repair shops, a limestone mine, processing mill and supporting functions and offices.
Generally the material and equipment is transported to the mine site by trams. The heavy duty equipment is transported using as lowboy through the HEAT road. This has proven to be the most vital infrastructure for transporting the type of equipment used at the open pit Grasberg mine (arif dwi cahyono)

Source : Seputar Indonesia, June 22, 2008