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Examples of Porphyry Copper Mines
Today 50-60% of copper and 95% of molybdenum production are from
porphyry mineralisation.

Chuquicamata Mine, looking across the pit 1993 through the
characteristic dust haze
Chuquicamata, Atacama, Chile
Some 1500km north of Santiago, Chuquicamata is located in the high
plain of the Atacama Desert, one of the driest places on earth.
For many years the world’s largest copper mine, Chuquicamata has
been in production continuously since 1910. Now owned and operated by
the state-owned miner Codelco, Chuquicamata may have contained as
much as 9000 million tonnes of ore and reserves and has produced
500,000 tonnes of copper and over 10,000 tonnes of molybdenum. Plans
are now to extend the life of the operation by starting underground
mining operations from 2015.
The nearby, and geologically similar, Escondida mine is now the world’s largest copper producer.
Grasberg, Irian Jaya, Indonesia
The enormous and remote Grasberg mine, is located in the western half of the island of Papua New
Guinea, in the Indonesian province or Irian Jaya. The operation has developed from the ground up with
all facilities, including transport links and town infrastructure being built by the American owner
Freeport McMorran Copper and Gold (67%) and Rio Tinto (13%).
Grasberg is the world’s largest gold mine and third largest copper mine. It was originally discovered by
geologists looking for the source of the rich alluvial gold deposits in the lowlands of Irian Jaya. Reserves
are estimated to include 2.8 billion tonnes of ore with grades of 1.1% copper 1.04 g/t gold 3.87g/t Ag
The series of porphyry ore bodies with sulphide-rich skarn mineralization at the margins. Chalcopyrite
is the dominant copper mineral, with three intrusive stages of mineralization identified.
The main pit is now a mile wide, and current operations are being extended underground as the open pit
reaches the end of life. An extensive underground mine 400m below the pit bottom is being developed
using block caving techniques.

Bougainville Copper Ltd, Papua New Guinea looking across the
pit – 1986

Bougainville Copper Ltd., Papua New Guinea
Once the world’s largest copper mine Bougainville has been
closed since 1989, when a local insurrection drove out the
Australian-based mining operation. However, the company is
still listed on the Australian stock exchange, and in 2012 Annual
Report the company claimed that they are in on-going talks to
reopen the mine.
The civil war killed 10-15,000 mainly local people, and
destroyed not only the mine and all it’s equipment but also the
mine’s milling plant, deep-water port and the company towns of Panguna and Arawa. BCL predicts that
it would take $2.5million to re-open Panguna mine site, including providing a power station,
infrastructure and tailings options Mine life 24 years producing 60 million tonnes ore annually, 180,000
tonnes copper 580,000 oz gold. Environment damage to the Jabiru River from mine tailings is one of the
many points of contentions with the local mine owners.
Epithermal Gold Deposits

Epithermal gold deposits are among the richest gold deposits in the world with some bonanza grade ore
shoots containing more than 1000 g/t gold, or in other words, a kilogram of gold for every tonne of rock

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