Report Verification



Being based in a gem centre like Jaipur, GTL is exposed to a range of unusual and bizarre gem materials submitted for identification. Because of the dedication and passion our staff gemmologists possess, these gem materials undergo a thorough research for their complete understanding. The results of such research are shared with the world through publications in various highly read gemmological journals of international repute.

In The Press


Choudhary G. & Vyas M.B. (2011) An exceptional rhodochrosite carving, Gems & Gemology, Vol. 47, No.3, pp 246-247

Rhodochrosite, a manganese carbonate known for its classic "rose" red colour, is often found as massive pink opaque or translucent specimen. The Gem Testing Laboratory, encountered a specimen that was remarkable for its size and fair degree of transparency. The specimen weighed 10.875 kg

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Choudhary G. (2011) A color zoned topaz, Gems & Gemology, Vol 47, No. 3, pp 250-251

The author reports on a transparent greenish brown specimen of topaz that was striking for its unusual colour zoning. The zoning pattern was reminiscent of a sapphire, however gemmological properties easily identified the sample as topaz. The angles of colour zones were around 40/140 degrees as against 60/120 degrees in a sapphire. This was the first time when the author encountered or seen a topaz with such distinct colour zoning pattern

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Choudhary G. (2011) Serpentine with purple-red transmission, The Australian Gemmologist, Vol. 24, No. 7, pp 164-166

One dark bluish green serpentine specimen weighing approximately 19.52 grams was encountered at the Gem Testing Laboratory Jaipur, India. The specimen was unusual for its crystal form and purple-red transmission in strong light. Serpentine, which is usually found as massive boulders, was seen here as a crystal with bladed habit and displayed fine striations on the surface due to cleavages. Further, this crystal also displayed a strong purple-red transmission in strong light; the effect was mistaken for colour-change effect and the sample was misrepresented as alexandrite.

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Choudhary G. (2011) Few remarkable stones tested at the Gem Testing Laboratory Jaipur, India. Presented at GIA International Gemmological Symposium 2011 held at Carlsbad, California on 29-30 May 2011. Abstract in proceedings volume.

Oriented needle-like inclusions were found in a flux-grown synthetic emerald. The needles appeared to be oriented along the prism faces; however, they intersected one another at approximately 60º. This synthetic emerald also contained numerous birefringent and elongated colourless crystals showing a hexagonal profile. A green quartz contained “lily pad”–like inclusions. The presence of colour zones/planes perpendicular to the optic axis indicated synthetic origin, which was confirmed by FTIR analysis. A dark bluish green serpentine was remarkable for its purple transmission in fiber-optic light. The exact cause of the purple transmission could not be determined, but it appeared to be the presence of minute particles arranged in planes. Other interesting materials included synthetic sapphire with natural-appearing milky zones, fluorite with corundum-like colour zones, and glass specimens with transparent crystals.

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