Hectorite is a rare soft, greasy, white clay mineral with a chemical formula of Na 0.3(Mg,Li) 3Si 4O 10(OH) 2.
Hectorite was first described in 1941 and named for an occurrence in the United States near Hector (in San Bernardino County, California 30 miles east of Barstow.) Hectorite occurs with bentonite from volcanic ash Hectorite is also found in the beige/brown clay ghassoul in Morocco A large deposit of hectorite is also found at the Thacker Pass lithium deposit, located within the McDermitt Caldera in Nevada. The Thacker Pass lithium deposit could be a significant source of lithium
Despite its rarity, it is economically viable as the Hector mine sits over a large deposit of the mineral. Hectorite is mostly used in making cosmetics, but has uses in chemical and other industrial applications, and is a mineral source for refined lithium metal.