Doublets and Triplets

What is a Doublet?

An opal Doublet is made up of a thin slice of opal glued onto a backing of either Boulder opal, volcanic glass (obsidian) or any other suitable black backing. Used to highlight, and bring out the colour of the opal.

Black opal is highly sort after because of its dark body tones which causes it's ingrained precious opal colour to be highlighted against its natural dark backing.

To try and clone this effect a thin slice of crystal or white opal is glued onto a black backing (slice of black potch or similar) this in turn makes the opal more vibrant.



Steps to making a Doublet –

- The crystal or white opal layer is generally shaped into a dome like shape, called a cabochon.

- The second layer is a black backing that is added to the underside of the opal. This can be made from black potch, black glass, brown ironstone, or sometimes black plastic.


What is a triplet?

A triplet consists of the same two layers as an opal doublet with the addition of a top layer that creates a cabochon effect as well as a protective layer.



Steps to making a triplet –

- A thin slice of opal which can be even thinner than the slice for a doublet to make up for the extra layer.

- A black backing the same as an opal doublet.

- The third layer is a clear domed shape that gives the stone a nice cabochon shape while creating a barrier that protects the opal. This layer is usually made out of a hard plastic, glass or quartz.

Caring for your doublet or triplet –

The thing to be careful about with opal doublets and triplets is that with prolonged water exposure the water can ingress between the different layers. This doesn’t mean you have to panic when you get a bit of water on your opal, it just means you wouldn’t want to be soaking it in water or other solutions for long periods. If water does start getting into the layers it can generate the appearance of condensation or foggy edges around the stone. To avoid the potential issue of prolonged water exposure when cleaning your opal doublet or triplet, a soft damp cloth with a mild detergent can be used to wipe the opal clean. Avoid chemicals, bleach and ultra-sonic cleaners when handling opal doublets and triplets.

How to identify a Doublet or Triplet?

To identify if an opal is a doublet or a triplet, the best way is to turn the piece on its side and have a look for lines between the layers of opal. The line (if doublet) or lines (if triplet) will be straight as the glue won’t hold properly otherwise. If it is already set in a piece of jewellery, then it is sometimes difficult to tell so you will have to trust the jeweler you are buying from.  You are unlikely to see any straight lines between layers in a solid opal as there is generally the natural irregularities of the host stone and opal.


Summary –

There is nothing wrong with doublets or triplets, more often than not they make some really beautiful pieces of jewellery. They can also give buyers an opportunity to purchase a nice opal piece that looks a lot like black opal but without the hefty price tag.  I rarely make doublets or triplets as we aim to sell only solid Australian opal.  If we do make the odd doublet or triplet it will be clearly labelled as exactly that. There’s nothing worse that someone falsely selling a doublet as a solid opal, it’s just ripping off people and gives the Australian opal industry a bad name.

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