The first prospecting expeditions visited the area in the 1860s and the first copper ore was concentrated in 1911. Miami is where the nation’s first “flotation” copper concentrator to process sulfide minerals was built and began production in 1915. Miami was among the first to employ “vat leaching” in 1926 and precipitation plants to recover oxide minerals. Copper was mined underground until after World War II, when the first open-pit mining began. The plant’s smelter was modernized in 1974 to meet Clean Air Act standards and further modernized and expanded in 1992. The success of a solution extraction/electrowinning plant commissioned in 1979 ended vat leaching by the mid-1980s and ultimately the concentrator in 1986 as well. The rod mill was commissioned in 1966.
In August 2015, the Company announced revised capital and operating plans in response to the recent decline in commodity prices. Subsequently, in mid-September, mining operations at Miami were suspended. Leaching/SX-EW operations will continue but are expected to decline over time. The Miami smelter and rod plant are not affected.
In 2016, copper production at Miami amounted to 25 million pounds of copper.
In 2017, copper production amounted to 19 million pounds and more than 740 people were employed here.
Miami Operations Fast Fact
- Miami operations are located 90 miles east of Phoenix, in Arizona’s historic Globe-Miami mining District
- Produces about 60 million pounds of copper cathode per year
- Processes about 690,000 tons of copper concentrate per year from Freeport-McMoRan operations producing about 400 million pounds of copper anode and 690 thousand tons of sulfuric acid for copper leaching at our North American mining operations
- In 2016, Miami operations direct and indirect economic impact on Arizona totaled $176.1 Million
- To learn about the various sustainable development projects at Miami, click here
- Miami has the following operations on site:
- An open-pit copper mine
- A solution extraction/electrowinning plant for the leaching process
- A smelter
- A rod mill