Laumontite

Laumontite is a mineral, one of the zeolite group. Its molecular formula is {Calcium}({Aluminium}{Silicon|2}{Oxygen|6})2·4H2O, a hydrated calcium-aluminium silicate. Potassium or sodium may substitute for the calcium but only in very small amounts. It is monoclinic, space group C2/m. It forms prismatic crystals with a diamond-shaped cross-section...
Found on http://en.wikipedia.org/wiki/Laumontite

Laumontite

• (n.) A mineral, of a white color and vitreous luster. It is a hydrous silicate of alumina and lime. Exposed to the air, it loses water, becomes opaque, and crumbles.
Found on http://thinkexist.com/dictionary/meaning/laumontite/

Laumontite

Lau'mont·ite noun [ From Dr. Laumont , the discoverer.] (Min.) A mineral, of a white color and vitreous luster. It is a hydrous silicate of alumina and lime. Exposed to the air, it loses water, becomes opaque, and crumbles. [ Written also laumonite .]
Found on http://www.encyclo.co.uk/webster/L/19

laumontite

common hydrated calcium and sodium aluminosilicate mineral in the zeolite family, formulated CaAl2Si4O124H2O. Its white to yellow or gray prismatic ...
Found on http://www.britannica.com/eb/a-z/l/21

Laumontite

Laumontite, named after its discoverer, Dr Laumont, is a form of anaclime (or analcite) with a powdery white surface. It is characterised by the fact that it is monoclinic. It has the formulae Ca(Al2Si4)O12ù4H2O and a relative hardness of 4. Exposed to the air, it loses water, becomes opaque, and crumbles.
Found on http://www.probertencyclopaedia.com/browse/HL.HTM
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