Opal: Natural vs. Lab: Is It Real or Fake?
Opal: Natural vs. Lab
Is It Real or Fake?
Originally stemming from the Sanskrit word upalas (meaning stone, jewel), then the Greek word opallios (meaning to see a change of color), the term we are familiar with today, Opal, has its roots in the Latin word opalus. A bit softer than quartz, and not quite as dense, Opal is hydrated silica and an amorphous mineral.
In its natural form, Opal consists of closely packed aggregate spheres of silica as silica oxide, and water in varying amounts up to 15%. These spheres are arranged in a series of layers allowing light to pass through, defracting at specific points, creating the play of colors that attracts us to Opals. The larger the spheres, the more vibrant the colors produced. Referred to as as common opals, are those which lack the colored sparkle of the precious opals, though both are used in jewelry.
Hitting the market in 1974, Lab Created Opals have found their rightful place in the World Gem Market. there are different references to these Opals including synthetic, simulated, and mosaic.
Mosaic Opal: is created from left over chips of Opal. Fitted together to form a new stone. Since the only involvement of man is the putting together of the puzzle pieces of actual opal, hardly qualifying as Lab Created.
Synthetic Opal: is created in a Lab, but its properties, chemical, optical and physical, are identical to that of a naturally occurring Opal.
Simulated Opal: is also created in a Lab, and is optically identical to natural Opal, but does not have the same physical and chemical characteristics.
One of the biggest distinctions, and subject of debate for classification, is what is used in place of water in the Lab Created Opals. The originator of the Synthetic Opal, Pierre Gilson Sr., uses pure silica to fill the gaps between the Opal spheres. Thus creating a product that is 100% Opal. Other manufacturers use a polymer-resin (epoxy glue), with only 70-90% of the stone being pure silica. Thus the question: do they qualify as synthetic or simulated Opal?
Whatever YOU decide, ALL varieties are quite beautiful! The simulated/synthetics are much hardier than their naturally occurring cousins, not so subject to temperature change, drying out, cracking or crazing. They can be, however, as expensive as the natural Opal, due to the long growing process (up to 2 years!). So, unless you are buying for investment purposes, find the stone you LOVE, and dont worry too much about the How (or Who) of its creation. Enjoy it simply for the pleasure it brings!