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Ghene Menezes

ALGT COLORED STONE IDENTIFICATION REPORT
IDENTIFICATION
Species .......................................................................................................... Natural Topaz
Variety .................................................................................................................. Blue Topaz
DESCRIPTION
Shape & Cutting Style ......................................................................... Oval, Mixed Cut
Measurements .................................................................. 21.26 x 16.57 x 10.25 mm
Carat Weight ................................................................................................... 31.34 Carat
Color ....................................................................................................................... Deep Blue
Transparency .................................................................................................. Transparent
ADDITIONAL GRADING CHARACTERISTICS
Trade Color Name ....................................................................................... London Blue
COMMENTS
Blue topaz is commonly enhanced by irradiation and/or heating to improve
its color. There is currently no scientific method available to determine
whether this gemstone has been enhanced or not.
30 June, 2025
73716522

Faceted gemstone

1 pcs  Blue Topaz  - 31.34 ct - Antwerp Laboratory for Gemstone Testing (ALGT) - London Blue

Gemstones

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Object

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Certification

International Gemological Institute (IGI)

International Colored Gemstone Association (ICA GemLab)

Antwerp Laboratory for Gemstone Testing (ALGT)

Instituto Gemólogico Español (IGE)

Gemological Institute of America (GIA)

Gem Report Antwerp (GRA)

Bellerophon Gemlab

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Asian Institute of Gemological Sciences (AIGS)

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Colour

Green

Blue

Yellow

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Bi-colour

Colourless

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Oval

Mixed cut

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Clarity

Eye clean

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Moderate

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Treatment

No evidence of treatment

No heat treatment

Oiling

Heat treatment

Commonly heated with no evidence of treatment

Not specified in the report

Clarity enhancement

Commonly irradiated with no evidence of treatment

Irradiation

Fracture healing / filling

No indication of treatments

Gemstone transparency

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Pearl luster

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Optical effect (gemstones)

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Gemstones

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1 pcs Blue Topaz - 31.34 ct - Antwerp Laboratory for Gemstone Testing (ALGT) - London Blue

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