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Gypsum is a common mineral, with thick and extensive evaporite beds in association with sedimentary rocks. Deposits are known to occur in strata from as far back as the Archaean eon. [16] Gypsum is deposited from lake and sea water, as well as in hot springs, from volcanic vapors, and sulfate solutions in veins.
Room and pillar mining of gypsum was used in Iowa beginning in 1892, and was phased out of use in 1927 due to low recovery and development of technologies that made surface mining more practical, safe, and cost effective. [4] More recently, the United States Gypsum Sperry mine, near Mediapolis, Iowa, opened in 1961. This room-and-pillar mine ...
The mine was initially owned by a Los Angeles company known as Blue Diamond, which began mining the land in 1925. An on-site processing plant was added in 1941, followed a year later by the construction of a nearby company town, known as Blue Diamond, Nevada. The mine was eventually sold to James Hardie Gypsum, which expanded operations in 1998.
USG has a large gypsum plant located 17 miles (27 km) west of El Centro, California, along highway Interstate 8, at Plaster City. [25] The Plaster City location makes Sheetrock brand gypsum panels. The gypsum is mined from a quarry located 20 miles (32 km) to the north, in the Fish Creek Mountains of Imperial County. The quarry is estimated to ...
Phosphogypsum is a by-product from the production of phosphoric acid by treating phosphate ore with sulfuric acid according to the following reaction: . Ca 5 (PO 4) 3 X + 5 H 2 SO 4 + 10 H 2 O → 3 H 3 PO 4 + 5 (CaSO 4 · 2 H 2 O) + HX
It is one of the six producers which hold approximately 81% of the worldwide wallboard market (Georgia Pacific, Knauf, Continental Building Products, National Gypsum, Saint-Gobain, and Yoshino Gypsum Co., Ltd) [5] Subsidiary National Gypsum (Canada) Ltd. operates the largest open-pit gypsum mine in the world in Milford Station, Nova Scotia.
The main sources of calcium sulfate are naturally occurring gypsum and anhydrite, which occur at many locations worldwide as evaporites. These may be extracted by open-cast quarrying or by deep mining. World production of natural gypsum is around 127 million tonnes per annum. [17]
Only one example of this sort of gypsum-mining remains in Paris, in a renovated "grotto" under the Buttes-Chaumont gardens. This method of burrowing was effective for the short-term, but over time the relatively soft mineral, subject to the elements and the earth's shifting, could erode or fissure, endangering the solidity of the mine.