Source : Webster's Revised Unabridged Dictionary (1913)

Stannine \Stan"nine\, Stannite \Stan"nite\, n. (Min.)
   A mineral of a steel-gray or iron-black color; tin pyrites.
   It is a sulphide of tin, copper, and iron.

Source : WordNet®

stannite
     n : a dark gray mineral with a metallic luster that is a source
         of tin [syn: {tin pyrites}]