AGTA Enhancement CodesWe disclose ALL gemstone treatments or enhancements. The "enhancement codes" that we have listed in our online catalog for each gem are explained below.
Definition: ENHANCEMENT = Any treatment process other than cutting and polishing that improves the appearance (color/clarity/phenomena), durability, or availability of a gemstone.
The following table describes the AGTA enhancment codes we use on our site.
For other codes visit www.agta.org .
If you have any questions about treatments that a specific gem
has undergone please contact us and we will gladly give you more
||The "N" symbol can be used for stones in the event that a stone has received no enhancement and the seller will provide a guarantee that there has been none.|
|F||Filling||As a by-product of heat enhancement, the presence of solidified borax or similar colorless substances which are visible under properly illuminated 10X magnification.|
|H||Heating||The use of heat to effect desired alteration of color, clarity, and /or phenomena. (Residue of foreign substances in open fractures is not visible under properly illuminated 10X magnification.|
|I||Infilling||The intentional filling of surface breaking cavities or fractures usually with glass, plastic, opticon with hardeners and/or other hardened foreign substances to improve durability, appearance and/or weight.|
|O||Oiling/Resin Infusion||The intentional filling of surface breaking cavities of a colorless oil, wax, natural resin, or unhardened man-made material into fissured transparent/translucent gemstones to improve appearance (i.e., oil, man-made resin, cedar wood oil, Canada balsam, paraffin, etc.).|
|R||Irradiation||The use of irradiation to alter a gemstone's color, may be followed by a heating process.|