It is important to differentiate the synthesis from the imitations. An imitation is a matter worked to imitate another stone, whereas a synthesis has the same chemical composition, the same crystalline structure as well as the same physical properties as a natural stone, except that it was manufactured by man.
Several processes are possible to create synthetic stones :
- By hydrothermal method
- By fusion in the flame (Verneuil)
- In a flux
- By pulling or method known as « Czochralski”
- By high pressure high temperature (HPHT)
- By chemical vapor deposit (CVD)
The affixing of the “synthetic” ranking is compulsory for the denomination of a matter which was created by man.