The Johnson Camp Mine is owned by Excelsior Mining Corp. and is located in a sparsely populated, flat to slightly undulating ranching and mining area about 105 road kilometers east of Tucson, Arizona.

Laramide age porphyry-related carbonate replacement deposits host oxide copper mineralization as mantos and breccias in Paleozoic carbonates. Modern mining and leaching operations at the Johnson Camp Mine, began in the 1970s by Cyprus Minerals. Successor owners and operators include Arimetco, North Star, Summo Minerals, and Nord Resources Corporation. Nord mined fresh material until mid-2010 and maintained leaching operations until late 2015, when the property was purchased by Excelsior.

Excelsior intends to restart operations of the historic Johnson Camp copper oxide open pits, and Excelsior expects copper cathode production will commence in the second half of 2022. Operations could provide up to 5 years of 25 million pounds per annum, which is the capacity of the existing SX-EW plant. The only additional infrastructure required to support future production are a new leach pad and minor piping and pumping facilities.