|Latitude & Longitude (WGS84):||31° 35' 34'' North , 111° 20' 33'' West|
|Latitude & Longitude (decimal):||31.59278,-111.34250|
|Other regions containing this locality:||Sonoran Desert, North America|
|Köppen climate type:||BSk : Cold semi-arid (steppe) climate|
Ref.: Keith, Stanton B. (1974), Arizona Bureau of Geology & Mineral Technology, Geological Survey Branch Bull. 189, Index of Mining Properties in Pima County, Arizona: 104 (Table 4).
Arizona Bureau of Mines file data.
MRDS database Dep. ID file #10109615, MRDS ID #M050508; and, Dep. ID #10259417, MAS ID #0040190097.
A former underground Au-Ag-Pb-Zn-Cu mine group located on 10 unpatented claims in North-central sec. 20, T.21S., R.10E., ½ mile N or Arivaca, on private land. Owned/operated at times, or in part, by the Amado Mining Co.; Oreona Mining Co.; Alba Mines, Inc.; Vogel Mining Co.; and, the Arivaca Mining Co. of Austin, TX (1956). Other long-term owners were the Oreona Development Co.
Mineralization is spotty argentiferous and auriferous galena and other sulfides in irregular quartz veins on fractures in Laramide granitic intrusives. The fissure veins range from one to 5 feet in width, and mineralized portions are up to 2 feet wide. The ore zone is 609.6 meters long and 1.52 meters wide, strikes N60E and dips 80N to vertical. Oxidation and enrichment occur near the surface. Comanche Shale is found west of the mine, and is overturned.
Workings include shaft and tunnel operations. Length of workings is 762 meters and depth is 67.06 meters. Three main shafts following veins include the Amado shaft, 220 feet deep and vertical; the La Caruva shaft, 125 feet deep and vertical; and, the No. 3 shaft and tunnel, 50 feet deep with a tunnel 600 feet long. Main tunneling extends 2000 feet east frem the Amado shaft. Worked mainly from 1921 through 1956, producing some 1,400 tons of ore averaging about 0.5 oz. Au/T, 6 oz. Ag/T, and a trace of Cu, 4% Pb, and 1% Zn.
Mineral ListMineral list contains entries from the region specified including sub-localities
5 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. 
|Tithonian - Toarcian|
145 - 182.7 Ma
|Jurassic granitic rocks|
Age: Jurassic (145 - 182.7 Ma)
Description: Granite to diorite, locally foliated and locally alkalic; includes Triassic(?) granitoids in the Trigo Mountains. This unit includes two dominant assemblages of igneous rocks. The Kitt Peak-Trigo Peaks superunit includes, from oldest to youngest: dark, foliated or gneissic diorite, medium-grained equigranular to porphyritic granodiorite, and small, irregular intrusions of light-colored, fine-grained granite. The Ko Vaya superunit, limited to south-central Arizona, includes texturally heterogeneous K-feldspar-rich granitic rocks. (150-180 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.