Ruby and Sapphire

Heat treatment was applied to the vast majority of rubies and sapphires to improve their color and/or clarity. The detection of heat treatment remains a troublesome issue in color stone industry. As it is known, with the same quality, rubies without any heating may command a high premium compared with heated rubies. Hence, the disclosure of heat treatment in a Gemological report is very important. Guild gem lab have established a very strong research team to focus on the classical and new heating methods applied to ruby and sapphire.  




Owing to their occurrence environment and their innate growth structure, emeralds are very commonly included with fractures, fissures and cavities. To avoid any possible chipping and cracking during cutting and polishing, the emerald roughs are usually put into certain type of oil to cover their fractures. Consequently, some oil may remain in the stone.

Presently, there are many type of “oil” filled in emerald, and fillers is the general term that refers to any material that are filled in emerald.Guild Gem Lab research team are conducting a long term project on the different type of fillers in emerald. And we are very happy to share our exciting results with any  in future.