Choudhary G. (2011) Pink cat's eye quartz, with color and chatoyancy caused by tourmaline needles, Gems & Gemology, Vol 47, No. 3, pp 245-246

The author describes an unusual occurrence of a quartz cat's whose colour as well as chatoyancy was caused by pink tourmaline needles. Tourmaline is quite often present in quartz giving rise to sagenetic variety, however in this case these tourmaline needles were present in one direction giving rise to chatoyancy. These tourmaline needles displayed their typical triangular cross section, which were further confirmed by infra red spectroscopy.

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

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

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.