AIGS Laboratory Disclosure Comments for Colored Gemstones

Ruby and Sapphire
(New codes are effective as of 01 June 2017)
 
Effect of Heat Treatment No Residue Found Residue Within Fissures Residue Within Cavities
Amount of Residue None Minor Moderate Significant Minor Moderate Significant
AIGS Disclosure Code "Indications of heating" (minor) (moderate) (significant) (1) (2) (3)
"Indications of heating" :  Basic heat treatment, but with no residue detected within cavities and/or fissures. Rubies and sapphires that have been subjected to high-pressure, high-temperature (HPHT) treatment are usually also given this classification.
 
(Lead) / (Bismuth) :   Lead and/or bismuth-rich, vitreous residue was encountered within the tested item’s fissures and/or cavities.
 
(SD) :   The item’s color has been altered via a surface diffusion process, whereby coloring ions have been allowed to penetrate the stone to a minute depth. While this artificial color is stable, it may be removed during any subsequent re-cutting and/or re-polishing.
 
(Light Elements) :   The item’s color has been subtley or significantly altered via a bulk diffusion process, whereby small coloring ions (e.g. beryllium, etc.) have been allowed to penetrate through the majority of the stone.
However, as the test for beryllium detection (i.e. LIBS) causes minor damage to the surface of a gemstone, this service is only carried out at the client’s request.
 
Jadeite
A-Jade :  No indication of enhancement beyond traditional and basic waxing.
B-Jade :  Indication of bleaching and subsequent polymer impregnation.
C-Jade :  Indication of dyeing.
 
Emerald
Clarity enhancement may be classified as “minor”, “moderate” or “significant”, depending on the amount of filling substances detected within the tested item’s surface-reaching cavities and/or fissures.
 
Identification of oil and/or resin is only carried out upon the client’s request, and charges may apply.
 
The following treatments are undetectable with current gemological tests. The presence or absence of these treatments will not be specified in our report.
 
- Heated or irradiated stones that are accepted in the trade:
     Spodumene (Kunzite, Hiddenite), Beryl (Aquamarine, Morganite), Tanzanite, Tourmaline, Topaz, Zircon, Quartz.
- Chemically treated stones:
     Dyed Chalcedony, Dyed Jadeite (of any color other than green), smoke or sugar treated Black Opal.
 
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