Word Study
anhydrite
CIDE DICTIONARY
anhydrite, n. [See Anhydrous.].
A mineral of a white or a slightly bluish color, usually massive. It is anhydrous sulphate of lime, and differs from gypsum in not containing water (whence the name). [1913 Webster]
OXFORD DICTIONARY
anhydrite, n. a naturally occurring, usu. rock-forming anhydrous mineral form of calcium sulphate.
Etymology
as ANHYDROUS + -ITE(1) 2
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