Sierra Gorda

The Sierra Gorda open-pit copper and molybdenum mine in Chile is a large mining project with a long-term operational perspective, commissioned in June 2014.

General Information

The Sierra Gorda mine is located in Chile – in the Atacama Desert in the Antofagasta region, approximately 60 km south-west of the city of Calama in the north of Chile, at an altitude of approximately 1700 m. The Catabela area is currently being exploited with a target mining depth of approximately 1000 m.



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

The mineralisation of Sierra Gorda was discovered in 2006, and since September 2011, the project has been a joint venture currently controlled by KGHM Polska Miedź S.A. (55%), Sumitomo Metal Mining (31.5%) and Sumitomo Corporation (13.5%).

Successive removal of the overburden in order to access the deposit began in 2012 and lasted for two years. The commissioning of the processing plant took place in 2014 and commercial production started on 1 July 2015.

As of 22 February 2022 KGHM has a new partner in the company Sierra Gorda SCM. Following the close of the transaction involving the sale of all of the shares held in this Chilean mine by Sumitomo Metal Mining Co., Ltd. and Sumitomo Corporation, the shares were transferred to the Australian mining group South32.



Mining processes include ore blasting, loading and transport by haul trucks to a processing plant with an average throughout of 110,000 tonnes of ore per day, where it is subjected to crushing and grinding processes. A plant with molybdenum concentrate separation is used for ore flotation. By optimising the use of existing infrastructure and necessary investments, the target annual average daily throughput of the processing plant will be increased.

The extracted oxide ore is stored for further heap leaching within the Sierra Gorda Oxide project.

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 areas.

Sierra Gorda operates with the use of seawater 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.

The latest and most effective technological solutions are implemented in production processes, following the current trends in the mining industry.

Financial statements of Sierra Gorda for Q1 2024 [PDF]