Pontatoc Mine (Pontotoc Mine), Tucson, Oracle District (Control District; Old Hat District; Santa Catalina District), Santa Catalina Mts, Pima Co., Arizona, USA
|Latitude & Longitude (WGS84):||32° 19' 56'' North , 110° 53' 52'' West|
|Latitude & Longitude (decimal):||32.3322222222, -110.897777778|
|Other regions containing this locality:||Sonoran Desert, North America|
A former small underground Cu-Ag-Au-Mo mine located in the NE ¼ sec. 3, T.13S., R.14E., at the South base of the Santa Catalina Mountains, in North Tucson. Discovered 1906. Owned/operated at times, or in part, by the Ponotoc Copper Co., Ramsdell; and the Texas-Arizona Copper Co. Owned by George Wilson (1964).
Mineralization is relatively weak, spotty, and localized copper minerals and minor molybdenite as ore in a wide altered breccia zone along the Catalina foothill fault dividing Catalina Gneiss, a Laramide metamorphic, from Tertiary to Quaternary Pantano conglomerate beds. The ore zone strikes N60E and dips 27SE. Ore occurred in the fault zones wherever rock alteration is intense. Alteration included silicification, propylitization, spordic dolomitization and epidote. Sulfides precipitated with quartz.
Assay revealed a maximum 10.3% Cu, average of 5% Cu. The dump assayed 2% Cu.
Local structures include a major E-trending fault zone and subsidiary faults; Santa Catalina Fault.
Workings include a 20 foot winze, a 105 foot deep shaft sunk between 1907-1910; and a 125 foot (38.1 meters) deep new shaft sunk around 1918, plus a pit and tunnel operations. Workings were ultimately 38.1 meters deep and 38.1 meters long. This mine was located in 1906 and worked in 1907 and 1916-1917. It produced a total of some 5,000 tons of hand-picked ore averaging about 4% Cu, 0.5 oz. Ag/T and a trace of Au.
14 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
|Middle Pleistocene - Tortonian|
0.126 - 11.62 Ma
|Early Pleistocene to late Miocene basin deposits|
Age: Cenozoic (0.126 - 11.62 Ma)
Description: Poorly sorted, variably consolidated gravel and sand that range widely in age. These sediments are generally light gray or tan. This unit is generally mapped in areas of deep late Cenozoic stream incision and landscape degradation where thin Quaternary deposits (map units Qy, Qm, Qo) discontinuously blanket older deposits (map units Tsy or Tsm) and the two cannot be differentiated at the scale of this map. (0.75-10 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. 
Moore, B.N., et al (1941), Geology of the Tucson quadrangle, Arizona, USGS Open-file Report.
DuBois, R.L. (1959), Petrography and structures of a part of the gneissic complex of the Santa Catalina Mountains, Arizona, Arizona Geological Society, Southern Arizona Guidebook II: 117-127.
Fair, C.L. & Jinks, J.E. (1961), Santa Catalina foothills fault in the Pontotoc area, Arizona Geological Society Digest: 4: 131-133.
Wilson, E.D. (1961): 61-62.
Medhi, P.K. (1964) A geologic study of the Pontatoc mine area, Pima County, Arizona: Tucson, University of Arizona, M.S. thesis, 44 p.
Banks, N.G. (1974) Field Examination (Pontatoc Mine).
Keith, Stanton B. (1974), Arizona Bureau of Geology & Mineral Technology, Geological Survey Branch Bull. 189, Index of Mining Properties in Pima County, Arizona: 113 (Table 4).
Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd. ed.: 166, 215, 284.
USGS (2005), Mineral Resources Data System (MRDS): U.S. Geological Survey, Reston, Virginia, loc. file ID #10039689, MRDS ID #M050656; and, Dep. ID #10234814.
DuHamel, Jonathan (2012), The Potatoc Mine in a north Tucson neighborhood, The Tucson Citizen, Wry Heat column, under geology (Jan 2, 2012).
Yale Peabody GNIS database (NOTE: this database is derived from USGS 1:24,000 topographic map data).
Arizona Bureau of Mines file data.
U.S. Bureau of Mines, Minerals Availability System (MAS) file ID #0040190364.