Hectorite

Hectorite is a soft, greasy clay mineral that forms near Hector, California (in San Bernardino County). The mineral is rare in that it is found primarily in one mine. The chemical composition of hectorite includes: sodium, lithium, magnesium, silicon, hydrogen and oxygen. Hectorite is mostly used in the manufacturing of cosmetics, but has uses in chemical and other industrial applications.
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General Information:
 Chemical Formula:
Na0,3(Mg,Li)3Si4O10(F,OH)2
 Locality:
Company No. 1 mine, 3 miles south of Hector, San Bernardino Co., California.
 Name Origin:
Named after it's locality.
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
white.
 Density:
2 - 3, Average = 2.5
 Diaphaniety:
Translucent to Opaque
 Hardness:
1-2 - Between Talc and Gypsum
 Luminescence:
Fluorescent.
 Luster:
Earthy (Dull)
 Streak:
white
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