Sierrita

Wholly owned open-pit copper and molybdenum complex in Pima County, Arizona, ~20 miles southwest of Tucson; in operation since 1959. Porphyry copper deposit with oxide, secondary sulfide and primary sulfide mineralization. Concentrator with 100,000 t/d design milling capacity producing copper and molybdenum concentrate; ROM oxide leach with cathode plated at the Twin Buttes EW facility (~50 Mlb/yr design). Molybdenum facilities include a leach circuit, two roasters and a packaging plant that also process concentrate from other FCX mines and third parties. Operation (incl. adjacent Twin Buttes site) covers ~50,500 acres. Net PP&E $1.0B.