The Carlota Mine is located in the western part of the United States in the Miami-Globe mining region of Arizona. The mine is surrounded by mountains and desert landscape.
The currently mined deposit was identified in the mid-1990s. After confirming the resources, several years were spent collecting baseline environmental, social, and geological data to understand the feasibility of the project and study potential impacts on the environment.
Production commenced in 2008 and the first copper cathode was produced in Q4 of the same year.
In 2014 mining operations from the open pit ceased. However, residual copper production continued utilising surface and sub-surface leaching using injection wells. In 2018, mining operations in the Eder South area resumed.
Extraction of copper ore from the Carlota mine is carried out using conventional methods typical for open pit mines, i.e. blasting and transporting the ore with haul trucks.
The production of copper in the Carlota mine is based on the solvent extraction and electrowinning (SX/EW) method which involves subjecting the ore to sulphuric acid. The pregnant leach solution (PLS) is pumped out of the heap and after the initial mechanical cleaning is subjected to the SX process, followed by the EW electrowinning process. The final products are copper cathodes.