Gold Occurrences in Chile

Coat of Arms of Chile
by B!mbo

Whenever anyone thinks of Chile they immediately think of copper since it is the largest producer of copper in the world, but many of the copper deposits have gold and silver as trace metals.  A recent statement by the Chilean Copper Commission (Cochilco) says their country’s production of gold could triple by 2015 making the country one of the top producers in the world.  Currently Chile’s gold production is pegged at 39.2 tonnes, however new developments and expansions of existing mines could cause output to swell to 103 tonnes by 2015.  This figure may be an underestimation as there are other gold mining projects waiting in the background.  Most of the gold produced in Chile comes from the production of copper as a byproduct.

There are several mining companies involved with this surge in gold production with the most notable being Barrick with its Pascua Lama project.  This does not include several other gold mining projects that are waiting in the wings.  Recent discoveries of gold/copper mineralization have been found in the high Andes that have become viable because of the high rise in gold and copper prices.  The biggest hurdle facing miners is the lack of or shortage of capital for developing these gold finds that sometimes can cost billions of dollars to get them into production.

Most of these projects in the high Andes are found above the 4,000 meter line making them difficult to mine as operations are hard on both personnel and equipment.  Some of these projects are centered on banded quartz projects carrying in places high anomalies of gold.  Other projects are to be found in gold bearing porphyry that has a lower gold content, but because of the vast volumes of rock present high tonnage, low grade projects.  At present the main target of the explorers is at La Falda that is a near-surface porphyry having associated epithermal gold-silver. 

Chile is not as famous for gold production then either Mexico or Peru exploration of the country by the Spaniards was financed with the placer gold that was discovered there.  In 1810 an the eve of its independence Chile was producing as much gold as Mexico and Peru combined.  In the 16^th century from the founding of Santiago in 1541 gold from placer deposits mainly in the southern part of the country produced up to 2 tonnes of gold annually. This mining came to an abrupt end when the Spaniards were evicted by the local Indians.

A second cycle of gold production started at about 1740 that were mainly based on vein mining.  The gold was recovered using trapiches and mercury to recover the gold.  This production peaked with the production of 3 tonnes in 1810.  There were several areas that were producing gold with the most prominent being located at Andacollo and other areas.  Gold production in all areas declined during the War of Independence that was finally reached in 1823.