|Latitude & Longitude (WGS84):||31° 43' 59'' North , 111° 40' 0'' West|
|Latitude & Longitude (decimal):||31.73306,-111.66667|
|Other regions containing this locality:||Sonoran Desert, North America|
|Köppen climate type:||BSh : Hot semi-arid (steppe) climate|
Ref.: Dale, V.B., Stewart, L.A., and McKinney, W.A. (1960), Tungsten deposits of Cochise, Pima, and Santa Cruz Counties., Arizona, U.S. Bureau of Mines Report of Investigation 5650: 78-81.
Keith, Stanton B. (1974), Arizona Bureau of Geology & Mineral Technology, Geological Survey Branch Bull. 189, Index of Mining Properties in Pima County, Arizona: 108 (Table 4).
MRDS database Dep. ID file #10009824, MRDS ID #D003057; and, Dep. ID #10039530, MRDS ID #M050227.
A former small surface W-Cu-Ag-Mo mine located in sec. 19 and North-central sec. 30, T.20S., R.7E., and secs. 24 & 25, T20S, R6E (protracted), about 2,000 feet NE of Chuivaya Well. Discovered 1951 by Mr. William H. Coplen. Owned at times, or in part, by Coplen; Shannon Mines, Inc.; and the Cinderra Mining & Engineering Co., Inc.
Mineralization is irrgular, disconnected quartz lenses with spotty scheelite and minor copper oxides in badly faulted Laramide quartzitic beds. Local skarn minerals and narrow aplite dikes. The ore strikes N-S and dips E to W. The quartzite bed is 4-6 feet thick. The scheelite occurs in discontinuous lenses.
The zoisite-bearing quartzite bed averaged 0.30% WO3 & 0.56% Mo03. The Grand Mountain claim averaged 0.19% WO3 & 0.04% Mo03. Ca-Al silicates inhibit magnetic separation of concentrates.
Workings include numerous open cuts and pits. Some 20 tons of low-grade copper-silver ore and about 50 tons of tungsten ore were produced in 1957.
6 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. 
|Holocene - Gelasian|
0 - 2.588 Ma
|Quaternary surficial deposits, undivided|
Age: Pleistocene (0 - 2.588 Ma)
Description: Unconsolidated to strongly consolidated alluvial and eolian deposits. This unit includes: coarse, poorly sorted alluvial fan and terrace deposits on middle and upper piedmonts and along large drainages; sand, silt and clay on alluvial plains and playas; and wind-blown sand deposits. (0-2 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.