Most gemstones are treated using various methods either to improve colour and clarity. Some of these methods are generally accepted in the trade today like oiling of emeralds, while other methods are not. The accepted trade methods are the ones that change the colour of the gemstone permanently.
Different Treatments are used for different stones considering their nature and reaction to it. Sapphires are commonly found heat treated as they react well to the treatment on different heating levels so one can get desired result from it. Some of them are
- Heat treatment
- Beryllium treatment
- Diffusion treatment
- Fracture filling treatment
- Laser drilling treatment
- Irradiation treatment
- Dying & Oiling
- HPHT
