Morenci is a census-designated place and company town in Greenlee County, Arizona, United States, and was founded by the Detroit Copper Mining Company of Arizona. The population was 2,000 at the 2000 census and 1,489 at the 2010 census. The biggest employer in Morenci and the owner of the town is Freeport-McMoRan, the owner of the Morenci Mine, the largest copper mining operation in North America, and one of the largest copper mines in the world.