Doublets and Triplets
Doublets and Triplets are opals that have been glued together to imitate the appearance of black opal. When a slice of opal is glued to a black backing, it causes the color to become much darker and more vibrant. Thus, doublets and triplets contain only a small amount of actual opal, and therefore, are much less valuable.
Doublets consist of two layers glued together. The top layer is genuine opal, while the bottom is generally vitrolite, black potch, ironstone, or hard plastic. Triplets, on the other hand, are like doublets, except the opal is generally much thinner, and the top layer is plastic, glass, or quartz. It is important to note that doublets are extremely hard to identify once set in jewelry, even for experts. Since the top is genuine opal, it looks exactly like black opal. Triplets, on the other hand, have a glassy appearance, and light reflects differently from the top of the gemstone.
Unlike solid opals, doublets and triplets should not be exposed to water, as it can get between the layers and cause the opal to take on a foggy appearance. Washing your hands is generally okay, but it's a bad idea to shower, swim, or wash dishes while wearing them. As with solid opal, keep them away from harsh detergents and only wash the tops with warm water and a non-abrasive pad or facial soap.
