Word Study
Iolite
CIDE DICTIONARY
Iolite, n. [Gr. 'i`on a violet + -lite.].
A silicate of alumina, iron, and magnesia, having a bright blue color and vitreous luster; cordierite. It is remarkable for its dichroism, and is also called dichroite . A variety called Caribbean iolite has a lighter blue color. [1913 Webster]
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