Sierra Gorda

The Sierra Gorda open-pit mine in Chile was commissioned in July 2014. Over the next 20+ years it will mine one of the deposits of copper and molybdenum.

General Information

The Sierra Gorda mine is located in copper basin in Chile – the Atacama desert in the Antofagasta region, approx. 60 km south-west of the town of Calama in northern Chile.


The Sierra Gorda mine operates on copper-molybdenum deposits, comprising both sulphide copper ore as well as an upper layer of oxide copper ore.

The deposit was discovered in 2006. KGHM INTERNATIONAL LTD. took over the project, which since 2012 has been a joint venture of KGHM International Ltd (55%), Sumitomo Metal Mining (31.5%) and Sumitomo Corporation (13.5%). 


Construction of the mine is being carried out in two stages. The first stage was completed in July 2014. It comprised the construction of a conventional open-pit mine (extraction using explosives and dump trucks, loading and transporting of ore for processing), infrastructure (including a tailings pond, power line and sea water pipeline) as well as a processing plant for the separation of molybdenum concentrate (high-pressure grinding rollers, ball mills and conventional floatation) with a processing capacity of 110 thousand tonnes of ore per day.

The oxide ore being stored for potential heap leaching. The copper concentrates produced by Sierra Gorda is transported to the port of Antofagasta, and from there by sea to smelters around the world. The mine also has exploration potential in adjacent terrain.

Sierra Gorda operates with the use of sea water from the cooling systems of a power plant in the town of Mejillones. Instead of being recycled to the sea, the water is pumped to the mine through a 144 km pipeline, which ensures an exceptionally efficient and ecological water procurement system.