Synthetic gemstones are artificially created gemstones that have the same chemical composition as their natural counterparts. They, therefore, harbor the same optical and physical properties as their natural counterparts. Under these conditions a well-known gem material like Cubic Zirconia, although artificial, is not a synthetic gemstone. Cubic Zirconia is therefore an imitation gem.
Synthetic gemstones carry the name of the natural stone with the prefix: ‘synthetic’, e.g. synthetic sapphire. There are several gemstone varieties that are known to have been synthesized, the most important ones are listed below:
- Beryl, including bright red beryl and neon Green Beryl which is used as a Tourmaline simulant
- Chrysoberyl, variety Alexandrite
- Corundum, including star corundum
- Diamond, all colors
- Forsterite, blue, used as a Tanzanite simulant1
- Quartz, all colors
- Spinel, all colors
In order to make the different artificial materials, different methods of synthesis are carried out. Most monocrystalline material is produced by one of the following methods:
- Crystallization from a melt
- Crystallization from a solution
- Examples: flux melt, hydrothermal method
To make diamonds enormous pressures are required and special techniques have been developed to achieve the synthesis of diamonds. These are called the Belt process and the Bars, or Split Sphere apparatus.
- Natural Forsterite isn’t used as a gem material, the artificial variety is never used to ‘fake’ natural Forsterite so it is always a simulant but since there is a natural counterpart the artificial variety falls under the ‘synthetics’.