Iolite
Pronunciation : I"o*lite
Part of Speech : n.
Etymology : [Gr. -lite.] (Min.)
Definition : Defn: 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.
Source : Webster's Unabridged Dictionary, 1913