A gemstone consisting of hydrated silica, typically semitransparent and showing varying colors against a pale or dark ground.
More example sentences
- The traditional kundan work has also been embellished with semi-precious and precious stones and beads such as tourmalines, tanzanites, opals, aquamarine and peridots.
- Diamonds and opals and onyx sat in lumps in the sparkling coloured windows.
- In a blinding flash the diamond, moonstone, opal, ruby and sapphire were molded together, inseparable, forever.