The Collaborative International Dictionary of English v.0.48:

Hematite \Hem"a*tite\, n. [L. haematites, Gr. ? bloodlike, fr.
   a"i^ma, a"i`matos, blood.] (Min.)
   An important ore of iron, the sesquioxide, so called because
   of the red color of the powder. It occurs in splendent
   rhombohedral crystals, and in massive and earthy forms; --
   the last called red ocher. Called also specular iron,
   oligist iron, rhombohedral iron ore, and bloodstone.
   See Brown hematite, under Brown.
   [1913 Webster]

WordNet (r) 3.0 (2006):

hematite
    n 1: the principal form of iron ore; consists of ferric oxide in
         crystalline form; occurs in a red earthy form [syn:
         hematite, haematite]