The first imitation opal was made by Pierre Gilson in the 1960s and first marketed in 1974. Gilson stone, as well as most other synthetic opals, contain an underlying honeycomb pattern that can be through a microscope. The stones can produce a full spectrum of colors.
Synonyms and Related Terms
Sources Checked for Data in Record
- Wikipedia, the free encyclopedia, at http://www.wikipedia.com Comment: http://en.wikipedia.org/wiki/Opal (accessed Oct. 12, 2005)
- Michael O'Donoghue and Louise Joyner, Identification of Gemstones, Butterworth-Heinemann, Oxford, 2003