Garcia Gypsum Mine (National Gypsum Co. Mine), San Pedro Valley, Lookout Mountain area, Pinal Co., Arizona, USA
Latitude: 32°49'53"N
Longitude: 110°41'21"W
A former surface gypsum mine located in secs. 10 & 14, T7S, R16E, on the E side of the San Pedro Valley, about 3¼ miles ESE of Lookout Mountain along the San Pedro River, about 7½ miles SSE of Dudleyville, and about 8½ miles N of Mammoth. Active in 1966. Operated by the National Gypsum Co.
Mineralization is a lacustrine gypsum deposit hosted in the Gila group.
The deposit may be extensive in area. It is exposed near the surface where mined, but buried to the S and E and eroded away to the W and N except in isolated residual hills. In this area, a zone at least 100 feet thick contains thick (1-8 feet), massive, white to grayish white, granular to microcrystalline, flat-lying gypsum beds. The gypsum beds are separated by thin layers of calcareous and gypsiferous shale and silt.
Assay data: White to grayish white, granular to microcrystalline gypsum beds. Grade varies but it is mostly 90% plus gypsum. Raw gypsum sold for agricultural purposes. Reserves and resources not estimated but probably in the multimillion ton range.
References
Blake, W.P. (1904) Gypsum Deposits of Arizona USGS Bull. 223 129 pp.
Stone, R.W. (1920) Gypsum Deposits of the United States, USGS Bull. 697, 326 pp.
Keith, Stanton B. (1969), Gypsum, in USGS & Arizona Bureau of Mines, and U.S. Bureau of Reclamation 1969, Mineral and water resources of Arizona, Arizona Bureau of Mines Bull. 180.
Phillips, K.A. (1987), Arizona Industrial Minerals, 2nd. Edition, Arizona Department of Mines & Minerals Min. Report 4, 185 pp.
Peirce, H. Wesley (1990), Arizona Geological Survey Industrial Minerals card file.
MRDS database Dep. ID #10060187, MRDS ID #TC10145.
Mineral List
1 entry listed. 1 valid mineral.
The above list contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please
register so you can add to our database. This locality information is for reference purposes only. You should never attempt to
visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders
for access and that you are aware of all safety precautions necessary.
Mineral and Locality Search
