Boehmite
| Boehmite | ||
|---|---|---|
2V angle Measured: 74° to 88°, Calculated: 80° | | |
| Dispersion | weak | |
| References | [2][3][4][5] | |
Boehmite or böhmite is an
specific gravity of 3.00 to 3.07. It is colorless in thin section, optically biaxial positive with refractive indices
of nα = 1.644 – 1.648, nβ = 1.654 – 1.657 and nγ = 1.661 – 1.668.
Boehmite occurs in tropical
hydrothermal alteration product of corundum and nepheline. It occurs with kaolinite, gibbsite and diaspore in bauxite deposits; and with nepheline, gibbsite, diaspore, natrolite and analcime in nepheline pegmatites.[4] Industrially, it is used as an inexpensive flame retardant additive for fire-safe polymers
.
It was first described by J. de Lapparent in 1927 for an occurrence in the bauxites of Mas Rouge, Les Baux-de-Provence, France, and named[6] for the Bohemian-German chemist Johann Böhm (1895–1952) who carried out X-ray studies of aluminium oxide hydroxides in 1925[7] (and not for the German geologist Johannes Böhm (1857–1938) as often stated).[2][3]
See also
References
- S2CID 235729616.
- ^ a b "Boehmite". Webmineral data. Retrieved 2010-07-10.
- ^ a b "Boehmite". Mindat with location data. Retrieved 2010-07-10.
- ^ a b Mineral Data Pub. Handbook of Mineralogy
- ^ "The Mineral Boehmite". minerals.net. Retrieved June 10, 2014.
- S2CID 129237343.
- .
