laumontite

Noun. (mineralogy) A mineral, of a white color and vitreous luster, with the chemical formula Ca Al₂Si₄O₁₂'''·'''4H₂O. It is a hydrous silicate of alumina and lime. Exposed to the air, it loses water, becomes opaque, and crumbles.

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This entry was last updated on RefTopia from its source on 3/20/2012.