Word Study
heulandite
CIDE DICTIONARY
heulandite, n. [After Heuland, an English mineralogist.].
A mineral of the Zeolite family, often occurring in amygdaloid, in foliated masses, and also in monoclinic crystals with pearly luster on the cleavage face. It is a hydrous silicate of alumina and lime. [1913 Webster]
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