Silver King Mine (Silver King Mining Co. property; Fortune Mine; California Mine; White Horse Mine; Seventy-Four Mine; Last Chance Mine), Comstock Wash, Kings Crown Peak area, Pioneer District, Pinal Mts, Pinal Co., Arizona, USA
|Latitude & Longitude (WGS84):||33° 19' 49'' North , 111° 5' 19'' West|
|Latitude & Longitude (decimal):||33.33028,-111.08861|
|Other regions containing this locality:||Sonoran Desert, North America|
|Köppen climate type:||BSh : Hot semi-arid (steppe) climate|
A former surface and underground Ag-Pb-Au-Cu-Zn mine located in sec. 24, T1S, R12E, in Comstock Wash, about 1 mile W of Kings Crown Peak, about 3 miles north of Superior. Discovered in the fall of 1874 and initially worked until Mar 24, 1875. Owned by Messrs. Long, Mason, Reagan & Copeland. During 1976-96 it was operated by the Silver King Mining Co. In 1916 the property was acquired by Silver King of Arizona Mining Co. Subsequently the property was acquired by Bat Gays who carried on small-scale operations. Previous operators include T. Gayo; Tritt Smelting and Refining; Silver King Syn.; Apache Silver; Silver King Arizona Mining; Dean Brothers; Silver King of Arizona Mining; and the Silver King Mining Co. During 1945-46 some of the area was prospected by diamond drilling. First produced 1877 and closed 1955. Owned by Dick Lobb and Grace Middleton (1982). Operated by Mr. John Reynolds (1987).
Also known as / designated: Patented claim MS 2052; Patented claim MS 2161; Patented claim MS 461; Patented claim MS 462.
The Silver King porphyry, in which was developed the Silver King orebody, crops out as an irregular mass approximately 2,500 feet long from east to west by 1,200 feet wide. It was intruded into the southeastern part of a much larger stock of quartz diorite.
Mineralization is hosted in Pinal Schist and in Silver King Quartz Diorite. Veinlets are interlaced in quartz diorite porphyry and Pinal Schist. The orebody formerly cropped out at the top of a little hill about 75 feet high, composedof uch altered yellowish-brown to greenish-gray porphyry. The orebody was apparently a compact plexus of veinlets inclosed in comparatively unfissured porphyry. Blake's description and the maps of underground workings show that the orebody was a stockwork about 130 feet in maximum diameter, with a general dip of 70º west. The stockwork was disposed about an irregular core or axis of milk-white quartz, containing some bunches of rich ore but as a whole comparatively barren. The ore consisted of altered porphyry traversed in all directions by innumerable veinlets carrying stromeyerite, tetrahedrite, galena, sphalerite, chalcopyrite and pyrite in a gangue of quatz with some baryte. Blake observed that stromeyerite and highly argentiferous tetrahedrite with ore or less acanthitewere the most important constituents of the ore on the upper levels, whereas argentiferous sphalerite had become the principal ore mineral on the seventh level.
The pit at the former outcrop of the orebody shows the brecciated quartz and porphyry. Extending N60-70E from the breccia mass is a steeply northeastward-dipping fissure which was mineralized for a few hundred feet along its strike. Evidence for other structural control of the breccia mass is not readily apparent. Ore control descriptions Silver King Quartz Diorite Porphyry dikes and stocks.
A legend concerning this mine is the story of the mine manager wearing a crown of interconnected native silver wires around his hat.
Original development was by open pit (115 x 92 x 120 feet). Workings in 1881 included a main shaft more than 600 feet deep, 5 levels, crosscuts & winzes. A 10-stamp mill was erected on the property. The old shaft (Bilk shaft) was ultimately 987 feet deep. A new shaft was sunk to 635 feet after 1916. There were several smaller shafts and open cuts. There were also 7 levels of workings. Workings are located on the present El Medico claim. Production was 5,943,157 oz. Ag, valued at $6,526,094 (1875-1889), and 232,764 oz. Ag valued at $252,674 (1918-1928) (period values).
34 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. 
|Ypresian - Campanian|
47.8 - 83.6 Ma
|Early Tertiary to Late Cretaceous granitic rocks|
Age: Phanerozoic (47.8 - 83.6 Ma)
Description: Porphyritic to equigranular granite to diorite emplaced during the Laramide orogeny. Larger plutons are characteristically medium-grained, biotite +/- hornblende granodiorite to granite. Smaller, shallow-level intrusions are typically porphyritic. Most of the large copper deposits in Arizona are associated with porphyritic granitic rocks of this unit, and are thus named 'porphyry copper deposits'. (50-82 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.