cuprite

from WordNet (r) 3.0 (2006)

cuprite
    n 1: a mineral consisting of cuprous oxide that is a source of
         copper

from The Collaborative International Dictionary of English v.0.48

Cuprite \Cu"prite\ (k?"pr?t), n. (Min.)
   The red oxide of copper; red copper; an important ore of
   copper, occurring massive and in isometric crystals.
   [1913 Webster]