ABSTRACT
The hydrometallurgical plant uses atmospheric ferric leaching technology, followed by SX-EW to produce copper cathode at a design production rate of 72,000 tonnes per year with a 91% recovery. An ongoing stockpile blending program helps smooth the plant feed grade. The deposit is a secondary sulphide mineral deposit formed by supergene enrichment in the up dip part of a massive primary sulphide zone. Near surface oxidation of the sulphide minerals to an iron oxide gossan, transport and precipitation of copper and finally replacement of unoxidized primary massive sulphides at depth formed the orebody. Subsequent
1 INTRODUCTION
Las Cruces is a copper open pit mine located 20 km. northwest of Seville, Spain and fully owned by Inmet Mining Corporation (Toronto, Canada). Las Cruces project is located in the eastern part of the prolific Iberian Pyrite Belt VMS district and is one of the highest grade copper deposits in the world. Original resource outlined was 17.6 million tonnes @6.2% Cu, equivalent to 1 million tonnes of contained copper. The Las Cruces mine has been in operation since 2009, having processed 1.4M tonnes in total as of December 31, 2011.
