Solid Opal – Aren’t they ALL Solid?
Solid opal is a term that has become known by mainly opal dealers and folks who understand a bit about opal because it intends to differentiate between the different ways opals are manufactured and presented.
Solid opals makes reference to the fact that the opal you are looking at is indeed a solid chunk of the gem as contrasted to the practice of slicing solid opal into slithers and setting them in a dark background.
Technically, the term ‘solid opal‘ has been replaced by the term “natural opal” in the official opal nomenclature that is now in vogue. In the considered opinion of the committee it was felt that the term is a bit confusing because really whether something is sliced, or left in a chunk, it is still a solid piece of opal. So to make things clearer, the replacement was recommended
The reason why Solid opal needs to be defined
Unlike most gemstones which are presented in one way, that is, found in the ground, trimmed and cleaned, and, in the case of faceted gems, put on a diamond flatting disk with a Dopstick holder that allows many small facets to be ground and polished. In the cash of gems with a cab or dome, the stones are put on a dop stick and fashioned into a cabochon (meaning “bald head” in French) The resultant gem is a solid piece of material, cut and polished.
The difference with Solid Opal
Solid opal can be presented in a number of different ways such as doublets or triplets. For a full description of this interesting system see our article solid, doublets and triplets, but basically what it means is that a solid opal chunk, as it comes out of the opal mines, can be sliced into slithers and set on to a black background, thus giving the opal a dark background which throws the color forward, making it more dynamic and vibrant.
This is when the slices of solid opal are attached to a black background and then the solid opal in the foreground is polished and the stone set. In this case, the solid opal is what you see when you look at your ring or pendant.
As you can see illustrated in the opalmine encyclopedia, solid opals that are sliced thinner and attached to a black background, are called triplets because a crystal cap is then attached to the top of the stone to protect it and give it a nice high dome, whereas opal doublets are usually quite flat. This is a way of getting really nice colors in opal at a very reasonable price so that opal becomes affordable to more people.
Solid Opals from Andamooka
Another type of solid opal (natural opal) is from the opal mining town of Andamooka. Some of the best quality crystal and dark opal comes from this mine and there is also a solid opal called “Andamooka Matrix” which is darkened with a carbon process to give a similar effect to black opal.
These solid opals are also of natural origin but they have been treated to make them more vibrant. However, they are still solid chunks of opal. They have not been sliced and set in a black backing.
Solid Opals from Queensland
This type of solid opal looks as though it has a dark brown backing cemented onto it but it is, in fact, a natural opal. The cutter, in this case, leaves some of the natural boulder ironstone on the back of the stone, and this again gives the appearance of a natural black opal that is presented as a solid piece. The solid opals are in fact categorized as black opals because of the effect of the dark boulder ironstone in the background.
In this case, the solid opal or ‘mother’ of the opal is the ironstone itself, and the little ‘babies’ or flecks of precious opal color are dispersed throughout the body of the stone and it is cut and polished in this natural state. These also have experienced a name change from “solid opal” to “natural opal”
Solid opal term replaced in the new opal nomenclature.
The many faces of solid opal
So in this discussion, you can see that opal is presented in a variety of different ways to suit everyone’s pocket. Opal is a unique stone and because of its special nature, the opportunity is opened up to many, both rich and poor, to enjoy the beauty of a solid opal.