Collahuasi mine
The Collahuasi or Ujina mine is a large copper mine located at altitude in the north of Chile in the Tarapaca Region. Collahuasi represents one of the largest copper reserves in Chile and in the world having estimated reserves of 3.93 billion tonnes of ore grading 0.66% copper. It lies about 15 km east of the copper mine of Quebrada Blanca.
The mine produced 560,000 tonnes of copper in 2018, making it one of the world's largest copper mines.
The ore concentrate produced in Collahuasi mine contain about 41% chalcopyrite, 18% chalcocite, 16% pyrite and 4% pyrrhotite.
In the 2020s the mine has faced difficulties relating to water scarcity and decreasing ore grades.
File:Ferrocarril en el salar de Ascotán, Chile, 2016-02-09, DD 46.JPG|thumb|left|FCAB ore train crossing the Ascotán salt flat at the mine
An early period of mining in Collahuasi occurred from about 1905 until 1930.