In 1995, the Magma Copper Company discovered a porphyry copper deposit beneath thick postmineral cover 2 km south of the historic Magma mine in Superior, Arizona. Since that time drilling has delineated a large, high-grade, hypogene copper-molybdenum deposit, now named the Resolution deposit, with an inferred resource of 1,624 million metric tons (Mt) at 1.47% Cu and 0.037% Mo.