Key to Grades

Ruby (R) / Blue Sapphire (B) / Yellow Sapphire (Y)
R-1.1, B-1.1, Y-1.1: Unheated.
R-1.2, B-1.2, Y-1.2: Unheated & Dyed. Color concentration is seen in surface reaching cracks.
R-1.3, B-1.3, Y-1.3: Oil-filling is seen in surface reaching cracks.
R-1.4, B-1.4, Y-1.4: Coated
R-2, B-2, Y-2: Heat Treated.
R-2.1, B-2.1, Y-2.1: Heat Treated along with Residue (flux) in surface reaching cracks and cavities.
R-2.2, B-2.2, Y-2.2: Heat Treated along with Glass Filling in surface reaching cracks and cavities.
R-2.3, B-2.3, Y-2.3: Heat Treated along with Residue (flux) & Glass Filling in surface reaching cracks and cavities.
R-2.4, B-2.4, Y-2.4: Heat Treated with titanium diffusion.
R-2.5, B-2.5, Y-2.5: Heat Treated with beryllium diffusion.
R-3, B-3, Y-3: Cavities filled with resin or some foreign substance.

Emerald (E)
E-1: Non – Treated
E-2.1: Oil filling is seen in surface reaching cracks.
E-2.2: Resin filling is seen in surface reaching cracks.
E-2.3: Resin & Oil filling is seen in surface reaching cracks.
E-3: Dyed. Color concentration is seen in surface reaching cracks.
E-4: Coated Beryl. Specimen is coated to improve it’s color and lustre.

Rest of the stones.
Initials of the Stone with code of treatment.
1. Coating – Specimen is coated to improve it’s lustre. E.g. Coated Quartz Q-1.3, Coated Topaz-To-1.3, etc.
2. Resin Filling – Some colorless material is seen in SRC’s & cavities to increase the durability / clarity of the stone. E.g. Turquoise T-1.5, Tanzanite Ta-1.5, etc.
3. Dyeing – Stone is color enhanced. Color concentration is observed in SRC’s. E.g. Dyed Quartz Q-1.2, Dyed Coral CO-1.2, etc.
4. Oiling – Oil filling is seen in SRC’s which is a common trade practice. Quartz Q-1.1, Topaz To-1.1, etc.
5. Glass Filling in Diamonds – Stone is Clarity Enhanced. Fracture filling with glass is seen. D-1.2.
6. Smoke / Sugar Treatment – Smoke / Sugar treatment has been done to improve the color and phenomenon of the stone. Only done on Opals. OSM-2.