Red Cloud Mine, Silver District, Trigo Mts, La Paz Co., Arizona, USA
|Latitude & Longitude (WGS84):||33° 6' 1'' North , 114° 35' 56'' West|
|Latitude & Longitude (decimal):||33.10028,-114.59889|
|Other regions containing this locality:||Sonoran Desert, North America|
|Köppen climate type:||BWh : Hot deserts climate|
A former surface and underground Pb-Zn-Ag-Au-V-Mo-Mn-Fe-Cu-Mn-Baryte-Fluorspar-W (Cl-Br) mine located in South-central sec. 2, T4S, R23W (protracted), on the W side of Red Cloud-Yuma Wash Road, at an altitude of approximately 750 feet, on private land. Owned at times, or in part, by the Red Cloud Mining Co. of New York (acquired prior to 1881); Horton & Knapp (1885- ); Messrs. Hubbard & Bowers; Red Cloud Consolidated Mines Co. (New York)(1917- ); E.R. Boericke (Primos) Co. (1925-26 - exploratory work); Neal Mining Co. (1928- ); Hanna; Penn Metals Inc.; Walter Riley & George Holmes (1948 - exploratory work); Penn Metals, Inc. (few months of 1941); and, the Red Cloud Mining & Milling Co. (1950).
Note: Old labels may show "Red Cloud mine, Yuma Co., Arizona" (Yuma Co. was later subdivided into the La Paz and Yuma counties.)
Mineralization is a vein deposit, irregular masses and vug linings of argentiferous lead and zinc carbonates with pyrolusite, vanadinite, wulfenite and minor malachite, nodules of partly altered argentiferous galena, and disseminated masses of silver chloride and bromide, in a gangue of iron oxides, quartz, fluorite, calcite, gouge and brecciated wall rock.
The vein occurs within an irregular fault zone which here strikes N.15ºW. and dips 35º to 60ºE., between Tertiary andesite breccia, dacite porphyry, rhyolitic to dacitic tuffs and lapilli tuffs and Laramide granodiorite to quartz diorite intrusive. Wall rocks are silicified, sericitized, and carbonatized. The best ore came from the intersections of fault and cross fractures. Average grade reported at 5-6% Pb and 10 oz. Ag/T.
Workings include a vertical shaft at 300 [see comment below] feet deep (1881) and a 274-foot incline, several open cuts and drifts. This is one of the earliest operations in the district, dating back to the early 1880's and patented in 1885. The total estimated and recorded production would be some 21,000 tons of ore averaging about 18 oz. Ag/T and 5.5% Pb and minor Au. Some Pb, Zn, and Ag were recovered from dumps in 1949. Worked from about 1979 to 1984. Recently claimed and worked as an open cut for specimens (2000-2003), wherein the overburden was stripped off of the vein for a considerable depth (now refilled).
[Comment by Donald McCoy (http://www.mindat.org/mesg-7-121556.html): "The summary states that the vertical shaft is 300' deep; In truth, the vertical shaft was originally 183' deep, intersecting the 270' level (which is actually 274' as is properly stated) on the vein. This distance is measured from the surface, down dip from the original surface hub, which was removed as a result of surface mining around the original portal. A decline runs from the bottom of the vertical shaft, down dip to the 503' level on the vein, with an additional vertical sump 12' into the water table at the bottom of the decline. The 1881 citation may indeed state that the shaft is 300', but that is incorrect. I personally measured the declines and shaft several times during construction which took place from 1977 through 1980. An additional full cross-section 10' vertical round was pulled from the bottom of the shaft in early 1979 to allow the top of a 5-ton ore skip to rest even with the 270 level."]
32 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
|Quaternary - Miocene|
0 - 23.03 Ma
|Cenozoic sedimentary rocks|
Age: Cenozoic (0 - 23.03 Ma)
Lithology: Sedimentary rocks
Reference: Chorlton, L.B. Generalized geology of the world: bedrock domains and major faults in GIS format: a small-scale world geology map with an extended geological attribute database. doi: 10.4095/223767. Geological Survey of Canada, Open File 5529. 
|Tortonian - Bartonian|
7.246 - 41.3 Ma
|Middle Miocene to Oligocene volcanic rocks|
Age: Cenozoic (7.246 - 41.3 Ma)
Description: Lava, tuff, fine-grained intrusive rock, and diverse pyroclastic rocks. These compositionally variable volcanic rocks include basalt, andesite, dacite, and rhyolite. Thick felsic volcanic sequences form prominent cliffs and range fronts in the Black (Mohave County), Superstition, Kofa, Eagletail, Galiuro, and Chiricahua Mountains. This unit includes regionally extensive ash-flow tuffs, such as the Peach Springs tuff of northwestern Arizona and the Apache Leap tuff east of Phoenix. Most volcanic rocks are 20-30 Ma in southeastern Arizona and 15 to 25 Ma in central and western Arizona, but this unit includes some late Eocene rocks near the New Mexico border in east-central Arizona. (11-38 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.