Castle Dome Mine (Castle Dome deposit; Pinto Valley deposit), Castle Dome area (Castle Dome Mine area; Pinto Valley Mine area), Inspiration, Miami-Inspiration District, Globe-Miami District, Gila Co., Arizona, USA
|Latitude & Longitude (WGS84):||33° 24' 28'' North , 110° 57' 17'' West|
|Latitude & Longitude (decimal):||33.40778,-110.95472|
|Other regions containing this locality:||Sonoran Desert, North America|
A former surface and underground Cu-Au-Ag-Mo-Rh-Fluorspar-Baryte-gemstone mine located initially on 8 patented claims, and subsequently on 37 claims, on Porphyry Mountain, in the W½ sec. 20 (and sec. 27 per MRDS), T1N, R14E (Inspiration 7.5 minute topo map), 5 miles W of Miami, on private land. Discovered 1881. Production began 1943 and mine closed December, 1953. Additional orebody underlying South Hill explored 1945-1946. Overburden removal commenced 1948. Owned by the Magma Copper Co. (1991). Claims were held by Castle Dome Development Co. from 1915-1924. The property was acquired by Pinto Valley Co. through merger in 1924. Pinto Valley acquired adjacent property bringing the total number of claims at Porphyry Mountain to 37. The property sold to Miami Copper Co. in 1940, which incorporated it as Castle Dome Copper Co., a wholly-owned subsidiary of Miami.
Mineralization is a disseminated copper porphyry deposit hosted in Lost Gulch Quartz Monzonite. The ore body was massive at 1460 meters long, 760 meters wide, and 335 meters thick, with a depth-to-top of 30 meters. It strikes N75E and dips 85S. Ore control was closely spaced, nearly parallel fractures striking N75E and dipping steeply south. Mineralization was stronger in the diabase sill and quartz monzonite adjacent sill. Ore concentration was a single hydrothermal event of short duration, oxidation, and supergene enrichment. Alteration was hydrothermal: weak propylitic, clay, quartz-sericite. The alteration phases are distinctly zoned, silicification. Turquoise was produced from the oxidized part of the deposit. Hypogene mineralization was confined principally to the quartz monzonite. Massive chalcopyrite is associated with the diabase sills.
Area structures include a NNW-trending horst of quartz monzonite and the Dome and Gold Gulch Fault systems.
Workings include an open pit - it mined the top of Porphyry Mountain. Early development was by means of shafts and tunnels which have been subhumed by pit operations. In 1990, in-situ and dump leach operations were conducted. Workings were 1828.8 meters in length and 914.4 meters wide. Production during the 10½ year life of the mine was fairly constant at 50 million pounds Cu per year. Total production was 514,390,317 pounds Cu, 8,291 oz. Au, 554,138 oz. Ag, obtained from 41,442,617 tons of ore.
45 valid minerals.
This geological map and associated information on rock units at or nearby to the coordinates given for this locality is based on relatively small scale geological maps provided by various national Geological Surveys. This does not necessarily represent the complete geology at this locality but it gives a background for the region in which it is found.
Click on geological units on the map for more information. Click here to view full-screen map on Macrostrat.org
1600 - 1800 Ma
|Early Proterozoic metasedimentary rocks|
Age: Statherian (1600 - 1800 Ma)
Description: Metasedimentary rocks, mostly derived from sandstone and shale, with minor conglomerate and carbonate rock. Includes quartz-rich, mostly nonvolcanic Pinal Schist in southeastern Arizona and variably volcanic-lithic sedimentary rocks in the Yavapai and Tonto Basin supergroups in central Arizona. (1600-1800 Ma)
Reference: Horton, J.D., C.A. San Juan, and D.B. Stoeser. The State Geologic Map Compilation (SGMC) geodatabase of the conterminous United States. doi: 10.3133/ds1052. U.S. Geological Survey Data Series 1052. 
Peterson, N.P., et al (1946), Hydrothermal alteration in the Castle Dome copper deposit, Arizona, Economic Geology: 41: 820-840.
Galbraith, F.W. (1947), Minerals of Arizona, Arizona Bureau of Mines Bull. 153: 19, 24.
Peterson, N.P. (1947), Phosphate minerals in the Castle Dome copper deposit, Arizona, American Mineralogist: 32: 574-582.
Schwartz, G.M. (1947), Hydrothermal alteration in the 'porphyry copper' deposits, Economic Geology: 42: 319-352.
Palache, C., Berman, H., & Frondel, C. (1951), The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana, Yale University 1837-1892, Volume II: 863.
Peterson, N.P., Gilbert, C.M., and Quick, G.L. (1951), Geology and ore deposits of the Castle Dome area, Gila County, USGS Bull. 971.
Creasey, S.C. (1959), Some phase relations in the hydrothermally altered rocks of porphyry copper deposits, Economic Geology: 54: 351-373.
Galbraith, F.W. & D.J. Brennan (1959), Minerals of Arizona: 43, 57, 64, 70, 72, 74, 99, 108.
Peterson, N.P. (1962), Geology and ore deposits of the Globe-Miami district, Arizona, USGS PP 342: 69, 70, 71, 73, 74, 75, 76, 77, 78, 88.
Simmons, W.W. & J.E. Fowells (1966), Geology of the Copper Cities Mine, in S.R. Titley and C.L. Hicks (eds.), Geology of the porphyry copper deposits, southwestern North America, University of Arizona Press, Tucson: 151-156.
Peirce, H.W. (1969), Gem Materials, in USGS & Arizona Bureau of Mines & US Bureau of Reclamation, Mineral and Water Resources of Arizona, Arizona Bureau of Mines Bull. 180 (USGS Bull. 871): 359-364.
Van Alstine, R.E. and Moore, R.T. (1969) Fluorspar, in Arizona Bureau of Mines Bull. 180 (USGS Bull. 871): 351.
Paydirt (1972) August 1972 (Mining Equipment).
Paydirt (1975) June, 1975 (Geology, etc.).
Mining Engineering (1975) June, 1975 (Geology, exploration, preproduction, concentration grade and product).
Mining Magazine (1975) November 1975 (Geology, exploration, water supply).
World Mining Yearbook, Catalog, Survey, and Directory Number (1975) June 25, 1975: 204 (1973 and 1974 production).
Burgin, L.B. (1976) Time Required in Developing Selected Arizona Copper Mines U.S. Bureau of Mines Information Circular 8702, Appendix B (history and production records).
Paydirt (1977) April 25, 1977 (Capacities).
Elevatorski, E.A. (1978), Arizona Industrial Minerals, Arizona Department of Mineral Resources, Minerals Report No. 2.
World Mining (1979) August 1979: 57 (1975-1978 production).
World Mining (1983) September 1983: 68 (1979-1982 production).
Phillips, K.A. (1987), Arizona Industrial Minerals, 2nd. Edition, Arizona Department of Mines & Minerals Mineral Report 4, 185 pp.
Peirce, H. Wesley (1990), Arizona Geological Survey Industrial Minerals card file.
Zaburunov, Steven A. (1990) Magma Independence: Old Resources, New Technology. Engineering and Mining Journal, January, 1990: C30-C35.
Phillips, K.A., Beard, R.R., Niemuth, N.J., and Bain, D.R. (1991) Active Mines in Arizona – 1992: Arizona Department of Mines and Mineral Resources Directory 39, 20 pp.
Niemuth, N.J. & K.A. Phillips (1992), Copper Oxide Resources, Arizona Department of Mines & Mineral Resources Open File Report 92-10: 7 (Table 1).
Sawyer, M.B., Gurmendi, A.C., Daley, M.R., and Howell, S.B. (1992) Principal Deposits of Strategic and Critical Minerals in Arizona, U.S. Bureau of Mines Special Publication, 334 pp.
Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd. ed.: 105, 112, 121, 125, 127, 132, 160, 163, 165, 179, 185, 190, 196, 213, 214, 220, 223, 228, 238, 248, 251, 261, 266, 276, 286, 296, 301, 304, 309, 336, 341, 358, 383, 386, 396, 404, 418, 431.
Singer, D.A., Berger, V.I., and Moring, B.C. (2005): Porphyry Copper Deposits of the World: Database, Map, and Grade and Tonnage Models. USGS Open-File Report 05-1060.
U.S. Bureau of Mines - Arizona Bureau of Geology and Mining Technology file data.
Arizona Department of Mines and Mineral Resources Primary Copper Industry of Arizona Special Reports Nos. 8-10 & 13 (1983-1986 production).
MRDS database Dep. ID #10027321, MRDS ID #M002863; and Dep. ID #10060273, MRDS ID #TC10276; and Dep. ID #10161463, MAS ID #0040070057; and Dep. ID #10209941, MAS ID #0040070061; and Dep. ID #10258292, MAS ID #0040070010.