Las Cruces is a high-grade open-pit copper mine and hydrometallurgical plant, owned and operated by Cobre Las Cruces S.A., a wholly-owned subsidiary of First Quantum Minerals Ltd. Las Cruces is located approximately 20 kilometers northwest of the city of Seville, in the Seville Province of southern Spain.
Construction of the mine was completed in 2008 and the process plant was completed in February, 2009. In June 2009, Las Cruces produced the first copper cathode.
The Las Cruces deposit is a polymetallic volcanogenic massive sulfide deposit, similar to other Iberian Pyrite Belt deposits. A thick, high-grade supergene zone overlies the primary sulfides, comprised of a gold-bearing gossan zone in the upper part and a copper-rich secondary sulfide zone underneath.
Las Cruces uses conventional open-pit mining methods, based on hydraulic excavators and trucks, with drilling and blasting in the lower marls and ore zones. Ore undergoes three stages of crushing, a single-stage of grinding and is thickened to eliminate water before it goes to three pre-reactor tanks.
The hydrometallurgical plant relies on a unique atmospheric ferric leaching process to recover copper from the rich Las Cruces chalcocite ore. The process, specifically designed for Las Cruces polymetallic ore, is optimized to produce London Metal Exchange (LME) grade copper cathode with minimal water and energy use, controlled liquid effluent and a dry solid waste stream.
The plant is designed to produce approximately 72,000 tonnes of copper cathode per year which is shipped as final product.
Royal Gold holds a 1.5% net smelter return (NSR) royalty on copper produced from the Las Cruces mine. The royalty is payable only when the London Metal Exchange (LME) cash settlement price for Grade A copper is equivalent or greater than $0.80 per pound of copper.
Royal Gold acquired its interest on February 22, 2010, with the acquisition of International Royalty Corporation, which included the 1.5% NSR royalty on Las Cruces.
*Detailed information on our interest can be found on the Portfolio Asset Summary table