Porphyry copper deposit in Arizona, United States

Names and other identifiers

Alternate names Cyprus Casa Grande
Tract name Western Sierra Madre Occidental and Laramide Central (003pCu3007x)
Site status deposit

Geographic location

Country United States
State or province Arizona
Geographic location -111.904722222, 32.523888889
Geologic map unit -111.904722222, 32.523888889
Nearby data

Geologic information

Deposit type Porphyry copper
Age (Ma) 66Ma
Age determination method unknown
Age range 66 Ma
Age reference Singer and others (2008)
Minerals brochantite, chalcocite, chalcopyrite, covellite, cuprite, diopside, garnet, goethite/limonite, magnetite, pyrite, tenorite, tremolite
Associated rocks quartz monzonite, quartz monzonite porphyry, skarn, andesite, conglomerate, diabase, fanglomerate, limestone, quartzite, schist, volcaniclastics
Tectonic setting continental margin
Stratigraphic age Late Cretaceous

Commodity and development information

Development status Occurrence
Major commodities Cu
Tonnage (Mt) 717Mt
Cu grade (%) 0.657%
Au grade (g/t) 0.17g/t
Ag grade (g/t) 1.2g/t
Contained copper 4,710,000t
Gold-Moly ratio -9999

Reference information

Comments 80% covered.
Study area name United States
References Einaudi (1982); Harper and Reynolds (1969); Johnston (1972); Long (1995); Singer and others (2008)
Site reference U.S. Geological Survey National Mineral Resource Assessment Team (2002)
Einaudi, M.T., 1982, Description of skarns associated with porphyry copper plutons, southwestern North America, in Titley, S.R., ed., Advances in geology of the porphyry copper deposits, southwestern North America: Tucson, University of Arizona Press, p. 139–183.
Harper, H.E., and Reynolds, J.R., 1969, The Lakeshore copper deposit: American Mining Congress Journal, v. 55, no. 11, p. 26–30.
Johnston, W.P., 1972, K-Ar dates on intrusive rocks and alteration associated with the Lakeshore porphyry copper deposit, Pinal County, Arizona: Isochron/West, no. 4, p. 29–30.
Long, K.R., 1995, Production and reserves of Cordilleran (Alaska to Chile) porphyry copper deposits, in Pierce, F.W., and Bolm, J.G., eds., Porphyry copper deposits of the American Cordillera: Tucson, Arizona Geological Society Digest 20, p. 35–68.
Singer, D.A., Berger, V.I., and Moring, B.C., 2008, Porphyry copper deposits of the world—Database and grade and tonnage models, 2008: U.S. Geological Survey Open-File Report 2008-1155, [45] p. and digital data, accessed December 31, 2013, at