Australian black opal ring

Ninety five percent of the world's opals are mined in Australia, mainly in Anda mooka, Coober Pedy, Lightning Ridge, Mintabie and other areas in NSW, SA and QLD.

• Black : Black opals have a rare body tone that often features an impressive play of colour.    
• White: More common white or milky opals , do not reflect colour as well and are often less valuable than black opals.   
• Boulder or matrix: Boulder opals , also called matrix opals, are a type of natural opal. They are mined in brown ironstone deposits. The opal is cut with the ironstone remaining in the back creating a unique and fashionable look.    
• Crystal: . They have a transparent to semi transparent state that tends to reflect a fair amount of colour. Crystal opals rank under the black opal in terms of rarity and value.    
• Fire: Rare red-orange fire opals are popular for their eye-catching colour.    
• Doublets: Doublets are a form of composite natural opal. The stone is actually made of two pieces, a solid piece of opal cemented to a black backing.
• Triplets: Triplet opals are made out of three pieces - a solid piece of opal, the black backing and a crystal cap cemented on the top.
• Synthetic and imitation: Synthetic opals are made of materials which have the same composition and physical structure but are man-made. Imitation opals simply just imitate the play-of-colour without having the physical or chemical structure as natural opals. Synthetic and imitation opals usually appear glassier than natural opals and have a precise and organised colour scheme, typically in a snakeskin pattern.