DISCLOSURE POLICY
Report wordings and nomenclature followed on GTL Identification Reports

GTL has formulated a system of disclosure of all types of treatments seen in the trade and points out on its identification reports in simple and clear wordings. These wordings / nomenclature are in accordance with the international guidelines laid down by the CIBJO and Laboratory Manual Harmonization Committee (LMHC). The disclosure policy is revised from time to time with the introduction of a new form of treatment or modification of an existing method.

CORUNDUM (Rubies and Sapphires)

Treatment Condition	Nomenclature	Report Wordings (Comments)
No heat A ruby or sapphire when do not exhibit any signs of heat treatment	Natural ruby / sapphire	No indications of thermal enhancement
Heating – No foreign residue A ruby or sapphire when display the features of heating	Natural ruby / sapphire	Indications of thermal enhancement
Heating – No conclusive features When no distinct features and / or proofs available to conclude the presence or absence of heating	Natural ruby / sapphire	Treatment has not been detected due to lack of evidence
Heating – Foreign residue A ruby or sapphire displaying the features of heating and presence of foreign substance / residues like Borax in fractures	Natural ruby / sapphire	Indications of thermal enhancement with heating residues (e.g. borax) in fissures, PLUS the extent of residue present as, TE1/TE2 (Minor) or TE3/TE4 (Moderate) or TE5 (Significant) - as the case may be
Heating - Foreign residue & glass filling in fissures / cavities Ruby or sapphire displaying features of foreign substance / residues (like Borax) as well as glass filling using lead, bismuth or silica with in cavities (moderate and significant quantity)	Natural ruby / sapphire	Indications of thermal enhancement with heating residues (e.g. borax) in fissures, PLUS, the extent of residue present as, TE1/TE2 (Minor) or TE3/TE4 (Moderate) or TE5 (Significant) - as the case may be In addition, clarity enhancement with lead/ bismuth / silica glass in fissures / cavities, PLUS, the extent of glass filler present as, F1 / C1 (Minor) or F2/C2 (Moderate) or F3/C3 (Significant) - as the case may be
Heating - Diffusion When a ruby or sapphire is coloured by surface diffusion	Natural ruby / sapphire (Artificially Coloured)	Thermal enhancement and colour modification just below the surface in a thin layer by diffusion of chemical(s) from an external source.
Heating - Diffusion (beryllium type)  When a ruby or sapphire display the signs of beryllium / bulk diffusion	Natural ruby / sapphire	Thermal enhancement and indications of diffusion of chemical (s) (e.g. beryllium) from an external source
Heating - Diffusion of star When the star effect is produced by diffusion treatment	Natural ruby / sapphire (Artificially Induced Star)	The star has been produced by diffusing inclusions just below the surface in a thin layer
Fracture Filling - Colourless glass Ruby or sapphire which displays the features of glass filling (colourless) using lead, bismuth or silica	Natural ruby / sapphire (Glass-filled*) * for lead / bismuth glass	Indications of clarity enhancement with lead / silica / bismuth glass in fissures / cavities, PLUS, the extent of glass filler present as, F1/C1 (Minor) or F2/C2 (Moderate) or F3/C3 (Significant) - as the case may be
Fracture Filling - Coloured glass Ruby or sapphire which displays the features of glass filling (coloured, e.g. blue / yellow) using lead glass	Natural sapphire (Glass-filled)	Indications of clarity enhancement with lead / silica / bismuth glass in fissures / cavities, PLUS, the extent of glass filler present as, F1/C1 (Minor) or F2/C2 (Moderate) or F3/C3 (Significant) - as the case may be In additions, Dyed with blue / yellow colour
Fracture Filling - Coloured oil When coloured oil (joban) is identified as the filler in fractures	Natural ruby / sapphire	Colour enhanced with red / blue colour in fissures, PLUS the extent of filling as, F2 (Moderate) or F3 (Significant) - as the case may be
Fracture Filling - Colourless oil When colourless oil /resin is identified as the filler in fractures	Natural ruby / sapphire	No indications of thermal enhancement. Oil in fissures identified

EMERALD / BERYL

Treatment Condition	Nomenclature	Report Wordings (Comments)
No Filling When no filler substance is present / identified	Natural Emerald	No indications of clarity enhancement
Fracture Filling - Oil When colourless oil is present in fractures	Natural Emerald	Indications of clarity enhancement with oil in  fissures, PLUS the extent of filler as, F1 (Minor) or F2 (Moderate) or F3 (Significant) - as the case may be
Fracture Filling - Resin When colourless resin is present in fractures	Natural Emerald	Indications of clarity enhancement with resin in fissures, PLUS the extent of filler as, F1 (Minor) or F2 (Moderate) or F3 (Significant) - as the case may be
Fracture Filling – Oil & Resin When a mixture of oil and resin is present in fractures	Natural Emerald	Indications of clarity enhancement with oil in fissures, PLUS the extent of filler as, F1 (Minor) or F2 (Moderate) or F3 (Significant) - as the case may be In addition, cavity filling with resin, PLUS the extent of filling as, C1 (Minor) or C2 (Moderate) or C3 (Significant) - as the case may be
Criteria used for quantification of filler Graphical illustration of quantification of filler with respect to size and number of filled fissures in emeralds – minor (left), moderate ( centre) and significant (right)
Fracture Filling – Coloured oil  When coloured oil (joban) is present in fractures in moderate to significant quantities	Natural Emerald	Colour enhanced with green colour in  fissures, PLUS the extent of filling as, F2 (Moderate) or F3 (Significant) - as the case may be
Fracture Filling - Dyed When light coloured beryl is dyed using colouring agents	Natural Beryl (Dyed)	None
Coating  When a beryl is coated with coloured or colourless substances	Natural Beryl (Coated)	This specimen has been coated with a thin film / layer which can be removed

DIAMOND

Treatment Condition	Nomenclature	Report Wordings (Comments)
Fracture Filling - Glass When a diamond is fracture filled with a glass	Natural Diamond	Indications of clarity enhancement with a glassy material in fissures, PLUS, the extent of glass filler present as, F1 (Minor) or F2 (Moderate) or F3 (Significant) - as the case may be
Laser Drilling When laser drill holes are seen but no glass is filled	Natural Diamond	Indications of clarity enhancement using laser drilling
Laser Drilling - Filled When laser drill holes are filled with a glass	Natural Diamond	Indications of clarity enhancement with a glassy material along laser drilled holes
HPHT (High Pressure High Temperature) When a diamond display signs of HPHT treatment	Natural Diamond	Indications of colour modification using High Pressure High Temperature (HPHT) process
Irradiation  When a diamond display signs of irradiation	Natural Diamond	Indications of colour modification using irradiation / heating processes
Heating  When highly included diamond show black graphitized areas along the fractures	Natural Diamond	Indications of colour modification using heating processes
Coating  If a diamond under test is identified as coated	Natural Diamond (Coated)	This specimen has been coated with a thin film / layer which can be removed

ALL OTHERS (EXCEPT CORUNDUM, EMERALD AND DIAMOND)

Treatment Condition	Nomenclature	Report Wordings (Comments)
Coating	Stone Name (Coated)	This specimen has been coated with a thin film / layer which can be removed
Colourless impregnation Using polymer / wax (porous stones like coral, turquoise, etc.)	Stone Name	Impregnated with colourless polymer / wax
Coloured impregnation using coloured polymers / dyes / waxes, etc	Stone Name	Impregnated with colourless polymer / wax
Dyeing When a light coloured stone is dyed to change the colour (when concluded)	Stone Name (Dyed)	None
Smoke / Sugar treated Opal	Natural Opal	Colour / phenomenal effect enhanced by smoke/ sugar treatment
Irradiation (Topaz – colour specific - for blues)	Topaz	This blue colour is produced by irradiation / heating processes
Heating Stones other than corundum (e.g. aquamarine, tanzanite, quartz, tourmaline, etc)	Stone Name	No Comment