semi-precious
Concise Oxford English Dictionary © 2008 Oxford University Press:
semi-precious
▶adjective denoting minerals which can be used as gems but are considered to be less valuable than precious stones.
'semi-precious' also found in these Oxford entries:
carnelian
- cat's eye
- gem
- gemstone
- hardstone
- jet
- marcasite
- moonstone
- onyx
- peridot
- pietra dura
- smoky quartz
- tiger's eye
- turquoise

