The term "crystal opal" refers to any kind of opal (black opal, semi-black opal, white opal) which has a transparent, translucent, or semi-translucent body. This is also referred to as the "diaphaneity" of a stone. If light is able to pass through the gemstone then you are probably looking at a crystal opal. Crystal opals can display any colour of the spectrum in a beautiful play of colour, fire and patterns. Some of my favourite opals to work with are crystal opals from Coober Pedy. They make stunning pendants, rings and earrings. You can check out our range of crystal opal for sale at www.OpalQuest.com.