chrysolite
    n 1: a brown or yellow-green olivine found in igneous and
         metamorphic rocks and used as a gemstone

Chrysolite \Chrys"o*lite\, n. [L. chrysolithos, Gr. ?; chryso`s
   gold + ? stone: cf. F. chrysolithe.] (Min.)
   A mineral, composed of silica, magnesia, and iron, of a
   yellow to green color. It is common in certain volcanic
   rocks; -- called also olivine and peridot. Sometimes used
   as a gem. The name was also early used for yellow varieties
   of tourmaline and topaz.
   [1913 Webster]