Antarcticite is an uncommon calcium chloride hexahydrate mineral with formula CaCl₂·6H₂O. It forms colorless acicular trigonal crystals. It is hygroscopic and has a low specific gravity of 1.715. As its name implies, it was first described in 1965 for an occurrence in Antarctica where it occurs as crystalline precipitate from a highly saline

brine Brine is a high-concentration solution of salt (NaCl) in water (H2O). In diverse contexts, ''brine'' may refer to the salt solutions ranging from about 3.5% (a typical concentration of seawater, on the lower end of that of solutions used for br ...

Don Juan Pond Don Juan Pond is a small and very shallow hypersaline lake in the western end of Wright Valley (South Fork), Victoria Land, Antarctica, west from Lake Vanda. It is wedged between the Asgard Range to the south and the Dais Range to the north. On t ...

, in the west end of Wright Valley, Victoria Land. This discovery was made by Japanese geochemists Tetsuya Torii and Joyo Ossaka.Antarcticite: A New Mineral, Calcium Chloride Hexahydrate, Discovered in Antarctica, Science 27 August 1965: Vol. 149 no. 3687 pp. 975-977
/ref> It was also reported from brine in

Bristol Dry Lake Bristol Lake is a dry lake in the Mojave Desert of San Bernardino County, California, northeast of Twentynine Palms. Bristol Lake is located southeast of Amboy, California, Amboy and U.S. Route 66 in California, U.S. Route 66, and is also south ...

, California, and stratified brine within blue holes on

North Andros Island North Andros is one of the 31 districts of the Bahamas. It is also the largest district (in area) in the country. It has some of the largest settlements on Andros Island and many churches as well. The population (2010 Census) is 3,898.

in the Bahamas. It has also been noted within fluid inclusions within quartz in

pegmatite A pegmatite is an igneous rock showing a very coarse texture, with large interlocking crystals usually greater in size than and sometimes greater than . Most pegmatites are composed of quartz, feldspar, and mica, having a similar silicic com ...

bodies in the

Bushveld complex The Bushveld Igneous Complex (BIC) is the largest layered igneous intrusion within the Earth's crust. It has been tilted and eroded forming the outcrops around what appears to be the edge of a great geological basin: the Transvaal Basin. It i ...

of South Africa. It occurs in association with halite, gypsum and celestine in the California dry lake. A similar mineral, ''sinjarite'', the dihydrate of calcium chloride, crystallizes in the tetragonal system. Sinjarite is semitransparent, with pale pink color. Hydrophilite is a now discredited calcium chloride mineral that is considered to be either antarcticite or sinjarite.Hydrophylite on Mindat
/ref>

References

Halide minerals Trigonal minerals Minerals in space group 150 {{halide-mineral-stub

See also

References