At the end of 2007 it had a total of reserves and resources of 118 million tonnes of copper in its mining plan, sufficient for more than 70 years of operation at current production rates.
[3][4] It also produces small amounts of gold and silver from refinery anode slimes, the residue from electro refining of copper.
The creation of the Corporación Nacional del Cobre de Chile, as it is currently known, was formalized by decree of April 1, 1976, under the Augusto Pinochet dictatorship.
It has several other potential mining operations under exploration and development including the Alejandro Hales, Gaby/Gabriela Mistral, the Toki Cluster, Mocha, and Casualidad projects.
[9] The modern era started when the American engineer Bradley finally developed a method of working low grade oxidised copper ores.
Their reports were good and in April 1911 he started to buy up mines and claims in association with Duncan Fox y Cia., an English entrepreneur.
[8][12] A port and oil-fired power plant were built at Tocopilla, 90 miles to the west and an aqueduct was constructed to bring water in from the Andes.
However their gradual depletion forced the construction of a mill and flotation plant in 1961 to treat the underlying secondary sulphides.
These have been steadily expanded until recently the pit was producing over 600,000 tonnes of copper annually, though this has now fallen with the lower grades as the richer secondary mineralisation is also depleted in the three porphyries that make up the orebody.
The present mine is a conventional truck and shovel operation, with a large proportion of the ore crushed in-pit and transported by underground conveyors to the mill bins.
It is estimated that extractable underground reserves below the present pit total 1,150 million tonnes of ore grading 0.76% copper and 0.052% molybdenum.
Two smaller areas of interest were found and the overall results showed that the Chuquicamata complex of mineralised porphyries is no less than 14 km long.
[19] Mining started in 1997 and is again a conventional truck and shovel operation followed by crushing, pre treatment and stacking before acid leaching.
It was initially estimated to have reserves of over 500 million tonnes grading over 1% copper,[20] but was found to be geologically complex and have a high arsenic content and work was stopped on it for some years.
[22] In 2005 Codelco had planned to shut down the El Salvador mine in 2011 because of declining ore grades and increased costs,[23] but extended the project life by an additional 15–20 years.
Originally owned by the American Cerro De Pasco Corporation, who brought the mine to production, it has been gradually built up by Codelco and is now the subject of a major expansion scheme.
[3] Work is now under way on the Andina Phase I Development Project which aims to raise mill capacity to 92,000 tonnes per day and is expected to be complete by November 2009.
[3] One of the mysteries of Andina is why it did not buy Compania Minera Disputada de las Condes when Peñarroya was prepared to sell it for a very low price in 1972.
[27] In November 2024, Codelco applied for an environmental permit for a $650 million project with aims to make water use in its Andlina mine more sustainable.
The Andina project in central Chile has faced a decade of drought and will require a maximum of 1,650 workers and take about 36 months to complete.
[17] However, these and subsequent attempts to establish anything more than a small scale mine failed for lack of capital and the property was eventually bought by the American, William Braden, for approximately US$100,000.
[10] Work started on establishing a mine in 1905 after Government permission had been acquired[29] but progress was slow because of difficulty of access and a hard winter climate.
The recent increase in mill capacity has been necessary to compensate for the gradual move of mining into the lower grade primary ore zone.
An independent company, Minera Valle Central, retreats old and current El Teniente tailings and extracts some 12,000 tonnes p.a.
[31] Sewell, the original mine camp and known as the 'city of stairs' because it looked as though it had been poured down the mountain, has become a UNESCO World Heritage Site.
Codelco sold a 51% interest in its El Abra deposit in 1994 to Cyprus-Amax (now part of Freeport McMoRan Copper and Gold) who then developed it.
Reserves are estimated at 580 million tonnes of oxide ore grading 1.41% copper and there is underlying sulphide mineralisation but this is not being considered at present.
It processes concentrates and anodes from Andina and El Teniente, amongst other producers, and makes Codelco increasingly self-sufficient.
On July 26, 2012, the Chilean and Ecuadorian government signed an agreement to activate the highly controversial Junin copper mining project, in the Intag area of Northwestern Ecuador.
The agreement calls for Codelco, jointly with the Ecuadorian national mining company- ENAMI- to begin exploration activities in the biodiverse Cordillera de Toisan after the second quarter of 2013.