Source : Webster's Revised Unabridged Dictionary (1913)

Cyanite \Cy"a*nite\ (-n?t), n. [See {Cyanic}.] (Min.)
   A mineral occuring in thin-bladed crystals and crystalline
   aggregates, of a sky-blue color. It is a silicate of
   aluminium. [Written also {kyanite}.]

Source : WordNet®

kyanite
     n : a gray or greenish-blue mineral consisting of aluminum
         silicate in crystalline form; occurs in metaphoric rock,
         used as a refractory [syn: {cyanite}]