| Los Pelambres mine | |
| Coordinates: | -31.7167°N -70.4904°W |
| State/Province: | Coquimbo Region |
| Country: | Chile |
| Products: | Copper |
| Opening Year: | 1990 |
Los Pelambres mine is a copper mine located in the north-central of Chile in Coquimbo Region. It is one of the largest copper reserves in the world, having estimated reserves of 4.9 billion tonnes of ore grading 0.65% copper.[1]
The deposit was first recognized by Willian Burford Braden in 1920. Production in 2012 was forecast at 390 tons of copper and 28,000 ounces of gold.[2] The mine is served by Los Pelambres Airport, and by a water desalination facility at Los Vilos. A billion-dollar expansion project is underway.[3]
The Upper Miocene tonalite stock is a north-south oriented oval, 4.5 by 2.4 km in size, which has undergone hydrothermal alteration. The stock intruded into andesitic host rocks. Glaciation during the Pleistocene carved the U-shaped Los Pelambres valley. The head of the valley has the highest concentration of ore in a roche moutonnee. A core of potassium silicate alteration contains the economic copper-molybdenum mineralization. Sulfide minerals include chalcopyrite, bornite, pyrite and molybdenite.[4]