Copper Cities Mine, Copper Cities Mine area, Sleeping Beauty Peak, Miami, Miami-Inspiration Mining District, Globe-Miami Mining District, Gila County, Arizona, USAi

Regional Level Types
Copper Cities Mine	Mine
Copper Cities Mine area	Area
Sleeping Beauty Peak	Peak
Miami	- not defined -
Miami-Inspiration Mining District	- not defined -
Globe-Miami Mining District	Mining District
Gila County	County
Arizona	State
USA	Country

A former surface and underground Cu-Mo-Ag-Au-gemstone-Zn-U-Pb mine located on the south flank of Sleeping Beauty Peak, 3½ miles north of Miami, straddling the middle part of the common boundary between the Globe and Inspiration quadrangles. Discovered 1896 and produced 1896-1982. Additional names which apply to this property: Porphyry Reserves.

Gold mining here started in 1896 by the Girard Mining Co. (Lost Gulch Mining Co. later). The Lost Gulch United Mines Co. was organized in 1909 to operate the properties of the Lost Gulch Mining Co.; reorganized as the Louis d-Or Gold Mining Co. in 1912 that worked the Bonanza, Badger & Cedar Tree claims for Au-Ag-Pb. About 1913 the Baldwin Syndicate of Chicago dispatched Charles E. Hart to examine these gold deposits. He concluded that a porphyry copper deposit was involved. The firm was reorganized as the Louis d'Or Mining and Milling Co. The Gila Monster, Bessie, and Sarah groups of claims covering the porphyry outcrops were optioned from J.W. Bennet. Exploration drilling began in 1917 and exploration continued until 1922 when the Louis d'Or shaft was sunk to the 360 level. The Bradley group of 5 patented claims was acquired in February, 1923. The company became insolvent in 1928 and the noteholders formed a new company jointly with the Pinto Valley Co., which was the Porphyry Reserve Copper Co. The company defaulted on bond interest payments in 1934. Copper Cities Mining Co., a new subsidiary iof the Miami Copper Co., purchased the surviving claims at sheriff's auction. Systematic exploration commenced in 1943 and was completed in 1948, confirming the extent of the orebody.

Mineralization is a porphyry copper deposit. Ore concentration was secondary enrichment. Alteration included quartz-sericite, argillic and weak propylitic processes.

This deposit is in a body of Lost Gulch quartz monzonite that has been intruded by several smaller bodies of granite porphyry. The outcrop of this quartz monzonite is a northeastward-trending horst block that is bounded on three sides by faults, the Sleeping Beauty fault on the NW side, the Ben Hur fault on the NE side, and the Miami fault on the east side. The south boundary of the mass is a steep intrusive contact with Pinal schist and the various rocks of the lower Precambrian dioritic complex.

The structures that are most important in their relation to the orebody are the Coronado and Drummond fault zones, which limit the copper orebody on the west and east sides, respectively.

The Coronado fault which strikes north and dips steeply west for a distance of 2,000 feet along the west side of the orebody, is a sheared, brecciated, and silicified zone, 100 to 300 feet wide. At the north and south ends of this broad part, the zone, trends westward and, in a distance of a few hundred feet, appears to contract to such a minor fissure that its outcrop is scarcely recognizable, but mining has exposed a strong gouge zone extending to the Sleeping Beauty fault. Where the fault zone is widest and most prominent, it is the boundary between the two facies of the quartz monzonite, the porphyritic quartz monzonite on the east, or footwall side, and the quartz monzonite porphyry on the west side. Small lenticular bodies of fine-grained diabase have been intruded along the fault zone.

The Drummond fault zone is much less prominent than the Coronado, but in other respects they are similar. The outcrop is a narrow zone of silicified breccia generally less than 25 feet wide. It strikes N.45ºW. and dips 60ºNE. It similarly forms the boundary between the two facies of the quartz monzonite along most of its recognizable length. Northeast of the Drummond fault zone, the quartz monzonite is traversed by many faults that strike north to NW and dip 50ºE. to vertical. Most of these faults are older than the diabase, and many of them have thin, discontinuous stringers or small irregular bodies of diabase intruded along them, particularly at the intersection of faults.

The mineralized quartz monzonite is intricately dissected by joints, fractures, and minor faults, some older and some younger than the period of mineralization. The older, or premineralization, fractures are now occupied by quartz-pyrite and chalcopyrite veinlets.

Other Databases

Link to USGS MRDS:	10027462

Localities in this Region

Other Regions, Features and Areas containing this locality

References