The Miami mine is a porphyry copper deposit that has leachable oxide and secondary sulfide mineralization. The predominant oxide copper minerals are chrysocolla, copper-bearing clays, malachite and azurite. Chalcocite and covellite are the most important secondary copper sulfide minerals.

Processes and facilities: Since about 1915, the Miami mining operation had processed copper ore using both flotation and leaching technologies. Current operations include leaching by the solution extraction/electrowinning (SX/EW) process. The design capacity of Miami's SX/EW plant is 200 million pounds of copper per year.