Hectorite

Phyllosilicate mineral in the smectite group

Hectorite is a rare soft, greasy, white, lithium-rich clay mineral with a chemical formula of Na0.3(Mg,Li)3Si4O10(OH)2. Hectorite was first described in 1941 and named for an occurrence in the United States near Hector, California (in San Bernardino County, California, 30 miles east of Barstow). Hectorite belongs to the smectite group; it is a swelling 2:1 clay mineral.

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