Empire District, Empire Mts, Pima Co., Arizona, USA

‡Ref.: The Resources of Arizona - A Manual of Reliable Information Concerning the Territory, compiled by Patrick Hamilton (1881), Scottsdale, AZ: 46.

Schrader, F.C. & J.M. Hill (1915), Mineral deposits of the Santa Rita and Patagonia Mountains, Arizona, USGS Bull. 582: 141-152.

Schrader, F.C. (1917) The geologic distribution and genesis of the metals in the Santa Rita-Patagonia Mountains, Arizona: Economic Geology, v. 12, no. 3, p. 237-269.

Galbraith, F.W. (1940) Gypsum: Arizona Bureau of Mines Circular 5, 6 p.

Wilson, E.D. (1941), Tungsten Deposits of Arizona, Geological Series No. 14, Arizona Bureau of Mines Bull. 148.

Galbraith (1949).

Wilson, E.D., et al (1951), Arizona zinc and lead deposits, part II, Arizona Bureau of Mines Bull. 158: 49-56.

Finnell, T.L. (1971), Preliminary Geologic Map of the Empire Mts quadrangle, Pima County, Arizona, USGS Open-file Report.

Keith, Stanton B. (1974), AZ Bur. of Geol. & Min. Technology, Geol. Survey Br. Bull. 189, Index of Mining Properties in Pima County, AZ: 117 (Table 4).

A Pb-Zn-Cu-Ag-Au-Mo-W-V mining area located in T.17-18S., R.17E., in the Empire Mountains, about 20 miles East of Tucson. Adjoined on the West by the Helvetia-Rosemont District. It extends from Davidson CAnyon eastward to Cienega Creek, 7 miles distant. The district contains 6 mining camps - the California, Montana, Lavery, Total Wreck, Copper or Hilton, and Prospect.

The dominant topographic feature in the district consists of the Empire Mountains, which form an outlier of the Santa Rita Range.

Mineralization is varied: (1) Replacement deposits of partly oxidized Pb-Zn-Cu minerals in Permian limestone and shale and in Cretaceous sedimentary formations, localized largely in badly faulted and overthrusted blocks and associated with strong faults and fissures. Some rhyolitic and dioritic dikes; (2) Contact metamorphic deposits of copper, tungsten and minor lead and molybdenum along the contact of Paleozoic limestone and Laramide intrusive; and, (3) Weak base metal sulfides along fissure veins in Laramide intrusive and Paleozoic quartzite.

Workings include numerous mines and prospects, mostly relatively shallow. Worked sporadically from about 1880 through 1964. Produced some 34,500 tons of ore containing about 172 tons of copper, 8,335 tons of lead, 258 tons of zinc, 740 oz. of gold, 206,400 oz. of silver and 76 tons of molybdenum.