"Opalite": Plastic Imitation Opal with True Play-Of-Colour
John I. Koivula and Robert C. Kammerling, March 1, 1989
A plastic imitation opal that shows true play-of-colour was advertised as "new" and offered for sale under the trade name "Opalite" at the Gem and Lapidary Dealers Association (GLDA) Tucson show in February 1988.
