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			Australian Opals - What are Solids, Doublets and Triplets?
	Solid opals are natural stones which have only been cut and polished. Many may have a natural rock backing. Doublets are made by cementing a layer of high grade opal to a black backing. This enhances the colour and makes them very attractive at a reasonable price. Triplets are doublets with an even thinner layer of opal, but with a clear domed cap, of either glass or quartz cemented on to the face. Doublets and triplets are valued at only a fraction of a solid stone.