semiprecious

from WordNet (r) 3.0 (2006)

semiprecious
    adj 1: used of gemstones having less commercial value than
           precious stones; "such semiprecious stones as amethyst,
           garnet, jade, and tourmaline"

from The Collaborative International Dictionary of English v.0.48

Semiprecious \Sem`i*pre"cious\ (s[e^]m`[i^]*pr[e^]sh"[u^]s), a.
   Somewhat precious; as, semiprecious stones or metals. Used
   mostly of gemstones used in jewelry, such as amethyst,
   garnet, or iolite, which are sufficiently rare to have
   commercial value, but are not considered as {precious}, as
   are the diamond, emerald, and ruby.
   [1913 Webster +PJC]