Red Mountain Mine (Red Mountain Copper prospect; Gem Mine; Carlton property; Ten Grand Mine; Red Mountain project), Red Mountain, Patagonia Mts, Santa Cruz Co., Arizona, USA
|Latitude & Longitude (WGS84):||31° 30' 12'' North , 110° 43' 6'' West|
|Latitude & Longitude (decimal):||31.50333,-110.71833|
|Köppen climate type:||BSk : Cold semi-arid (steppe) climate|
|Other regions containing this locality:||Sonoran Desert, North America|
A former small surface and underground Cu-Al-Zn-Pb-Mo-Au-K-Clay mine located in the center of the SW¼ sec. 21, T22S, R16E, 2.5 miles SE of Patagonia, on National Forest land. Discovered 1970 (Cu). Owned and operated by Kerr-Mc Gee Oil Industries, Inc., Earth Sciences, Inc. (1966). Claims extend into sections 20 and 17, on the northern and eastern slopes of Red Mountain. USBM gives section as 20 and longitude of 110-44-14W.
Mineralization is a porphyry copper deposit with hypogene enrichment of fractured intrusives. Gossan and some oxidized copper on surface indicates surface ozidation and leaching. Felsic volcanic rocks are pervasively altered solfatarically. Ore control was disseminations of chalcopyrite, bornite, and molybdenite in porous fractured intrusives at great depths. Alteration is high pyritic phyllic alteration surrounded by pyritic-argillic and propyllitic alteration. With depth sulphur decreases and changes from near-surface sulphur-rich phyllitic alteration, through weak potassic alteration, to low-sulphur potassic alteration at depth. Alunitization and silicification.
Significant copper mineralization encountered from 3410 feet to 5194 feet below surface. Alunite deposits found near surface in an area of 4000-5000 acres. The average copper and associated molybdenite ore zone thickness is 455 feet. Alunite deposit dimentions: maximum length of 10,000 feet; maximum width of 6000 feet; and a maximum thickness of 800 feet. Structure is a collapse caldera with intrusive source of Cu mineralization. Supergene enriched chalcocite blanket overlies the primary chalcopyrite.
The Red Mountain volcanics have been correlated with the Gringo Gulch Volcanics to the north and west, which give above K/Ar dates. The Red Mountain Volcanics overlie trachyandesite of Meadow Valley dated at 72.1 +/- 2.2 M.Y. (Simons, F.S., 1974). Basal contact between tuffaceous volcanics and underlying trachyandesite is roughly horizontal. The thickness of the Red Mountain Volcanics is estimated at 1500 feet.
Local structures. In the Patagonia Mountains the dominant structural features are major NW-trending, high-angle faults. This includes the Harshaw Creek Fault. The Patagonia Fault is a major NE-trending fault. E-W and N-S-trending faults are found in Tertiary volcanics.
Tectonic elements include the Red Mountain Fault Block with downthrow to the north.
Analytical data, including X-ray, chemical, and thin section data indicate variable tenor of alunite with considerable kaolinite, pyrophyllite, and sericite locally. Pb exceeds 100 ppm in high pyrite alteration zones, diminishing with depth; Mo exceeds 20 ppm throughout phyllic alteration zones; Zn averages 20-100 ppm in a near-surface leached zone; chalcopyrite increases with depth, averaging 0.1-0.7% Cu.
Workings extend to a depth of 138.68 meters. Kerr-McGee conducted deep drilling exploration for Cu ore; Earth Science conducted shallow percussion drilling exploration for alunite. Red Mountain interests comprise 289 unpatented claims (151 under option from W.D. Roper, 45 from A. Desaulles, 11 from J. Yanez, 4 from Carlton Spalding, 93 claimed by Kerr-McGee). Diamond drilling was conducted by Sexton Brothers drilling contractors, Metler Brothers Drilling Co., and the Joy Drilling Co.
Workings included over 10 drill holes for copper exploration, a few over 1000 feet deep, and a 688 foot exploration tunnel into the mountain. Workings on the Ten Grand claim included a 1500 foot tunnel. Alunite exploration consisted of surface drilling only (no mining).
19 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
|Ypresian - Campanian|
47.8 - 83.6 Ma
|Early Tertiary to Late Cretaceous volcanic rocks|
Age: Phanerozoic (47.8 - 83.6 Ma)
Stratigraphic Name: Williamson Canyon Volcanics
Description: Rhyolite to andesite and closely associated sedimentary and near-surface intrusive rocks; commonly dark gray to dark greenish gray or greenish brown. In the ranges west of Tucson, this unit includes thick welded ash-flow tuffs. Volcanic rocks of this unit are inferred to be derived from vents and volcanoes above magma chambers that solidified to form the granitic rocks of map unit TKg. These rocks are restricted to southeastern Arizona except for a small outcrop near Bagdad. (50-82 Ma)
Comments: Related, broadly, to unit TKg
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. 
Mines Magazine (1970) Nov. 1970.
Pay Dirt (1970) September 28, 1970.
Drewes, H.D. (1971) Mesozoic stratigraphy of the Santa Rita Mountains, southeast of Tucson, Arizona: U.S. Geological Survey Professional Paper 658-C, 81 p.
Simons, F.S. (1972) Mesozoic stratigraphy of the Patagonia Mountains and adjoining areas, Santa Cruz County, Arizona, in Mesozoic stratigraphy in southeastern Arizona: U.S. Geological Survey Professional Paper 658-E, p. E1-E23.
Simons, F.S. (1974) Geologic map and sections of the Nogales and Lochiel quadrangles, Santa Cruz County, Arizona: U.S. Geological Survey Miscellaneous Investigations Series Map I-762, 9 p., 1 sheet, scale 1:48,000.
Corn, R.M. (1975) Alteration-mineralization zoning, Red Mountain, Arizona: Economic Geology: 70(8): 1437-1447.
Raup, R.B. (1975) Geologic Map Elgin Quadrangle.
Pay Dirt (1975) March 24, 1975.
Tucson Daily Citizen (1975) February 22, 1975.
World Mining (1976) October 1976.
Skillings Mining Review (1977) 3-26-1977.
Hall, R.B. (1978) World Non-bauxite Aluminum Resources – Alunite. USGS Professional Paper 1076-A: A14.
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.: 107, 216.
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 Land Management Mining District Sheet #721.
U.S. Bureau of Mines files - Red Mountain Mine, Red Mountain project.
MRDS database Dep. ID file #10048337, MRDS ID #M899921; and, Dep. ID #10137861, MAS ID #00402230027.