www.gem-passion.com

by Gagan Choudhary

gagan’s bibliography

  • Choudhary G. (2023) New yellow to gray-brown opals from Australia. Presented at the IGC-37 conference, Tokyo, Japan. Abstract in proceedings.
  • Choudhary G. (2022) Flux-healed and glass-filled rubies – new challenges. Presented at the 7th International Gem & Jewelry Conference (GIT 2021). Abstract in proceedings.
  • Choudhary G. (2019) Recent challenges in identification of filled emeralds. Presented at the IGC-36 conference, Nantes, France. Abstract in proceedings.  
  • Choudhary G. & Vijay S. (2019) A review of commercially available turquoise imitations. Presented at the IGC-36 conference, Nantes, France. Abstract in proceedings.  
  • Choudhary G. (2019) Glass-filled Polki-cut CVD Synthetic diamond. Gems & Gemology, Vol. 55, No. 2, pp 288-289
  • Choudhary G. (2018) Emerald: Resin-filled fissures with ‘oil-like’ films – concerns and challenges. InColor Magazine, Issue 40, pp 100-104
  • Choudhary G. (2018) Green-blue Maxixe-type beryl. Gems & Gemology, Vol. 54, No. 2, pp 236-237
  • Choudhary G. (2018) 3161cm-1 feature in synthetic yellow sapphire. Presented at the GIA’s 2018 Gemmological Symposium, Carlsbad, USA. Abstract in proceedings.
  • Choudhary G. (2017) AquapraseTM: An interesting green-blue variety of chalcedony. Presented at the IGC-35 conference, Windhoek, Namibia. Abstract in proceedings.  
  • Choudhary G. (2016) Polymer-treated Hessonite. Gems & Gemology, Vol. 52, No. 1, pp 102
  • Choudhary G. (2015) Coral Inclusions in Plastic. Gems & Gemology, Vol. 51, No. 3, pp 341-342
  • Choudhary G. (2015) A Shattuckite Briolette. The Journal of Gemmology, Vol. 34, No. 7, pp 566-567
  • Choudhary G. (2015) Fracture-filled Synthetic Emerald, with Quartz Inclusions. The Journal of Gemmology, Vol. 34, No. 6, pp 483-484
  • Choudhary G. (2015) Emeralds from Jharkhand – an update. Presented at the IGC-34 conference, Vilnius, Lithuania from 26-30 August 2015. Abstract in proceedings  
  • Choudhary G. (2015) Purple Scapolite. Gems & Gemology, Vol. 51, No. 2, pp 202-203
  • Choudhary G. (2015) Peridot-Polymer Composite. The Journal of Gemmology, Vol. 34, No. 5, pp 25-26
  • Choudhary G. (2015) Attractive Composite Quartz Beads. Gems & Gemology, Vol. 51, No. 1, pp 106-107
  • Choudhary G. (2015) A Remarkably Large Amblygonite-Montebrasite Carving. Gems & Gemology, Vol. 51, No.1, pp 98-99
  • Choudhary G. (2015) What’s in a name – mystification over terminology for synthetic gems. http://www.gem-passion.com
  • Choudhary G. (2014) Emeralds from Jharkhand. Presented at the GIT 2014 conference, Chiang Mai, Thailand from 8-9 December 2014. Abstract in proceedings volume
  • Choudhary G. (2014) Aquamarine with Unusually strong Pleochroism. Gems & Gemology, Vol. 50, No. 3, pp 244-245
  • Choudhary G. (2014) Emeralds Partially Coated with Amorphous Carbon. The Journal of Gemmology, Vol. 34, No. 3, pp 242-246
  • Choudhary G. (2014) Synthetic Ruby Doublet with a Natural-appearing Sheen. The Journal of Gemmology, Vol. 34, No. 2, pp 110-111
  • Choudhary G. (2014) Dyed Bone as a Red Coral Imitation. Gems & Gemology, Vol. 50, No. 2, pp 164-166
  • Pradat T. & Choudhary G. (2014) Gem-quality Cr-rich kyanite from India. Gems & Gemology, Vol. 50, No. 1, pp 87-88
  • Choudhary G. (2014) Yellow sapphire filled with lead glass. Gems & Gemology, Vol. 50, No. 1, pp 92-93
  • Choudhary G. (2013) An ornamental sapphirine – cordierite – sillimanite rock from South India. The Australian Gemmologist, Vol. 25, No. 4, pp 146-151
  • Choudhary G. (2013) Greenish Blue Spodumene. Gems & Gemology, Vol. 49, No. 4, pp 258-259
  • Choudhary G. & Fernandes S. (2013) Inclusions in Indian Rubies. Presented at International Gemmological Conference (IGC) 2013 held in Vietnam from 12 -19 October 2013. Abstract in proceedings volume.
  • Choudhary G. (2013) Boron Carbide – A new imitation of black diamond. Gems & Gemology, Vol. 49, No. 3, pp 180-181
  • Choudhary G. (2013) Corundum carving coated with colored polymer. Gems & Gemology, Vol. 49, No. 3, pp 184-185
  • Choudhary G. (2013) Violet and Pink coated opals. The Australian Gemmologist, Vol. 25, No.2, pp 55-57
  • Choudhary G. (2013) Turquoise- rock crystal composite. Gems & Gemology, Vol. 49, No. 2, pp 123-124
  • Choudhary G. (2013) Orangy pink coated “soft coral”. Gems & Gemology, Vol. 49, No. 2, pp 121
  • Choudhary G. (2013) Bottled Up: An interesting incident with an RI contact fluid bottle. Gems & Jewellery, Vol. 22, No.2, pp 12-13  
  • Choudhary G. (2013) Dumortierite- quartz rock presented as sapphire. Gems & Gemology, Vol. 49, No. 1, pp 59-60
  • Choudhary G. (2013) Zoned scapolite from India. Gems & Gemology, Vol. 49, No.1, pp 58-59
  • Choudhary G. (2013) Opal- calcite composite. Gems & Gemology, Vol. 49, No. 1, pp 55-56
  • Choudhary G. (2012) An overview of inclusions in Indian Gemstones. Presented at the GIT Conference 2012 held at Bangkok, Thailand on 12-13 December 2012
  • Choudhary G. (2012) Green and orangy yellow calcite from Pakistan, Gems & Gemology, Vol. 48, No.3, pp 217-218
  • Choudhary G. (2012) Golden coral. Gems & Jewellery, Vol. 21, No.2, pp 12-13
  • Choudhary G. (2012) Coated quartz imitation of rubellite tourmaline. Gems & Gemology, Vol. 48, No. 2, pp 154-155
  • Choudhary G. (2012) Dioptase from Mozambique. The Australian Gemmologist, Vol. 24, No.9, pp 215-219
  • Choudhary G. (2012) A dyed blue opal with play-of-colour. Gems & Gemology, Vol. 48, No.1, pp 69-70
  • Choudhary G. (2011) Quartz with acicular emerald inclusions. Gems & Gemology, Vol. 47, No. 4, pp 323
  • Choudhary G. (2011) Composite malachite plates. Gems & Jewellery, Vol. 20, No. 3, pp 3-5
  • 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
  • Choudhary G. & Vyas M.B. (2011) An exceptional rhodochrosite carving. Gems & Gemology, Vol. 47, No.3, pp 246-247
  • Choudhary G. (2011) A color zoned topaz. Gems & Gemology, Vol 47, No. 3, pp 250-251
  • Choudhary G. (2011) Serpentine with purple-red transmission. The Australian Gemmologist, Vol. 24, No. 7, pp 164-166
  • 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.
  • Choudhary G. & Fernandes S. (2011) Spectroscopic examination of commercially available quartz varieties- a gemmological perspective. Presented at GIA International Gemmological Symposium 2011 held at Carlsbad, California on 29-30 May 2011. Abstract in proceedings volume.
  • Choudhary G. (2011) Plastic coated quartz, imitating emerald. Gems & Gemology, Vol. 47, No. 1, pp 71-72
  • Choudhary G. (2010) A greenish yellow zoisite. The Australian Gemmologist, Vol. 24, No. 4, pp 90 – 91
  • Choudhary G. (2010) And now composite chalcedony. Gems & Jewellery, Vol. 19, No. 4, pp 28 – 30
  • Bhandari R. & Choudhary G. (2010) Update on Mexifire synthetic fire opal. Gems & Gemology, Vol. 46, No. 4, pp 287 – 291
  • Choudhary G. (2010) A strongly thermoluminescent spodumene. Gems & Gemology, Vol. 46, No. 4, pp 322 – 323
  • Choudhary G. (2010) Glass with crystalline aggregates. Gems & Gemology, Vol. 46, No. 4, pp 328 -329
  • Choudhary G. (2010) Various chatoyant stones – an overview. Midlands Focus, 17th issue, pp 15 – 17
  • Choudhary G. (2010) New types of glass- with deceptive crystalline inclusions. Midlands Focus, 15th issue, pp 3-5
  • Choudhary G. (2010) Another interesting composite – diamonds and rock crystal. Gems & Jewellery, Vol. 19, No. 3, pp 12 – 13
  • Choudhary G. (2010) Glass imitations of emerald with straight zones. Gems & Gemology, Vol. 46, No. 2, pp 155-156
  • Choudhary G. (2010) A new type of composite turquoise. Gems & Gemology, Vol. 46, No.2, pp 106-113
  • Choudhary G. (2010) A chatoyant malachite. Australian Gemmologist, Vol. 24, No.2, pp 44-45
  • Choudhary G. (2010) New inclusions with crystal glass. Journal of Gems & Gemology, Issue 2, pp 43-45 (In Chinese with English abstract)
  • Choudhary G. (2010) A new type of composite. Gems & Jewellery, Vol. 19, No.1, pp 12-14
  • Choudhary G. (2010) A Be-diffused sapphire with interesting zoning patterns. Gems & Gemology, Vol. 46, No.1, pp70
  • Choudhary G. (2009) Dyed pink alabaster. Gems & Gemology, Vol. 45, No. 4, pp 309 – 310
  • Choudhary G. (2009) Synthetic sapphires with ‘natural-like’ sheen. Gems & Jewellery, Vol. 18, No. 3, pp 6-9
  • Choudhary G. (2009) “Smoky” gray beryl. Gems & Gemology, Vol. 45, No.3, pp 216 – 217
  • Choudhary G. (2009) Serpentine cat’s eye. Gems & Gemology, Vol. 45, No. 2, pp 151-152
  • Fernandes S. & Choudhary G. (2009) Gem quality andalusite from Brazil. Gems & Gemology, Vol. 45, No. 2, pp 120-129
  • Choudhary G. & Vyas M.B. (2009) ‘Multiphenomenal’ quartz from India. Gems & Jewellery, Vol. 18, No. 1, pp 10-12
  • Choudhary G. (2009) Interesting natural and synthetic spinels. Gems & Gemology, Vol. 45, No.1, pp 68-70
  • Choudhary G. (2009) Aventurine K-Feldspar. Midlands Focus, 14th issue, pp 13 – 17
  • Choudhary G. (2009) Tairus Created Gems: Part I – Beryl. Journal of Gems & Gemology, Issue 1, pp 28-30 (In Chinese with English abstract)
  • Choudhary G. (2009) Various Remarkable stones tested at Gem Testing Laboratory, Jaipur, India. Presented at the GIT 2nd International Gem and Jewelry Conference held in Bangkok, Thailand, March 9-12, 2009. Abstract in proceedings volume.
  • Choudhary G. & Golecha C. (2008) Note from the laboratory – Anglesite, an unusual collector’s gemstone. Australian Gemmologist, 23, 314-315
  • Choudhary G. (2008) Purplish blue synthetic quartz. Gems & Gemology, Vol. 44, No. 4, pp 377 – 379
  • Choudhary G. (2008) Multi-coloured synthetic quartz. Gems & Jewellery, Vol. 17, No. 3, pp 14-16
  • Choudhary G. (2008) Two interesting synthetic rubies. Gems & Gemology, Vol. 44, No.3, pp 279 – 281
  • Fernandes S. & Choudhary G. (2008) A tourmaline crystal within a crystal. Gems & Gemology, Vol. 44, No.3, pp 272 – 273
  • Choudhary G. (2008) An interesting zoned sapphire crystal from Winza, Tanzania. Gems & Gemology, Vol. 44, No.3, pp 270-272
  • Choudhary G. & Bhandari R. (2008) A new type of synthetic fire opal: Mexifire. Gems & Gemology, Vol. 44, No.3, pp 228 – 233
  • Choudhary G. (2008) Innovative composites ‘Fusion’. Gems & Jewellery, Vol. 17, No. 2, pp 20- 22
  • Choudhary G. (2008) A sapphire with en echelon inclusions. Gems & Gemology, Vol. 44, No. 2, pp 180-181
  • Choudhary G.(2008) An interesting opal. Gems & Gemology, Vol. 44, No. 2, pp 172- 174
  • Choudhary G. & Golecha C. (2008) ‘Paraiba’ tourmaline and similar looking materials. Gems & Jewellery, Vol. 17, No. 1, pp 16 -18
  • Choudhary G. (2008) Lead glass-filled colour-change sapphire. Gems & Gemology, Vol. 44, No. 1, pp 88 -89
  • Choudhary G. (2008) An interesting synthetic sapphire. Gems & Gemology, Vol. 44, No. 1, pp 87-88
  • Choudhary G. (2008) Aventurine K-Feldspar. Journal of Gems & Gemology , Issue 3, pp 20-22(In Chinese with English abstract)
  • Choudhary G. (2008) Synthetic emerald necklace. Midlands Focus, 13th issue, pp 5-7
  • Choudhary G. & Golecha C. (2007) A remarkably large clinohumite. The Journal of Gemmology, Vol.30, No.5/6, pp 303-306
  • Choudhary G. & Golecha C. (2007) Now synthetic beryl simulating “Pariaba” from Tairus. Gems & Gemology, Vol. 43, No. 4, pp 385 -387
  • Choudhary G. & Golecha C. (2007) An unusual YAG with a “reverse” colour change. Gems & Gemology, Vol. 43, No. 4, pp 387 -388
  • Choudhary G. & Khan M. (2007) A remarkably large fire opal carving. Gems & Gemology, Vol. 43, No. 3, pp 258 – 259
  • Choudhary G. & Golecha C. (2007) A study of nail-head spicule inclusions in natural gemstones. Gems & Gemology, Vol. 43, No. 3, pp 228 – 235
  • Choudhary G. & Golecha C. (2007) Some convincing glasses. Gems & Jewellery, Vol. 16, No. 3, pp 6 -8
  • Choudhary G. (2007) Glass masquerading as ulexite. Midlands Focus, 11th issue, pp 5 -6
  • Choudhary G. & Golecha C. (2007) Synthetic star sapphire with hexagonal features. Gems & Gemology, Vol. 43, No. 2, pp 177 – 178
  • Choudhary G. (2007) Glass object with circular bands. Gems & Gemology, Vol. 43, No. 2, pp 174 – 175
  • Choudhary G. & Golecha C. (2007) Emerald with unusual growth features. Gems & Gemology, Vol. 43, No. 1, pp 66- 68
  • Choudhary G. (2007) Ruby in serpentine – a new carving medium. Midlands Focus, 10th issue, pp 24- 25
  • Choudhary G. (2006) The Essence of Emerald. First Impressions, Jaipur Jewellery Show
  • Choudhary G. & Golecha C. (2006) Diffusion treated synthetic sapphire with unusual fluorescence. Gems & Gemology, Vol. 42, No. 4, pp 287- 289
  • Choudhary G. & Golecha C. (2006) Circular ring-like inclusions in a diffusion –treated sapphire. Gems & Gemology, Vol. 42, No.4, pp 286-287
  • Choudhary G. (2006) Unusual composites. Midlands Focus, 9th issue, pp 19 – 22
  • Choudhary G. & Golecha C. (2006) Trapiche – the fixed star. Gems & Jewellery, December 2006, pp 122-123
  • Choudhary G. & Vyas M.B. (2006) Natural sapphire with unusual inclusions. Gems & Gemology, Vol. 42, No. 2, pp 179 – 180
  • Choudhary G. (2006) Two unusual star emeralds. Gems & Gemology, Vol. 42, No. 2, pp 171-172
  • Choudhary G. (2006) Sapphire with unusual colour zoning. Gems & Gemology, Vol. 42, No.1, pp 74-75
  • Choudhary G. (2006) Plate tectonics and the gemstone deposits. Midlands Focus, 8th issue, pp 13 -21
  • Choudhary G. (2005) An unusual emerald with conical growth features. Gems & Gemology, Vol. 41, No.3, pp 265 – 266
  • Choudhary G. (2005) Yellow hydrothermal synthetic sapphires seen in India, Gems & Gemology, Vol. 41, No.2, pp 182
  • Choudhary G. (2005) Tanzanite buyers beware! Midlands Focus, 6th issue, pp 12-13
  • Choudhary G. (2004) Are treatments only for natural stones. Midlands Focus, 5th issue, pp 16-18
  • Fernandes S. Khan M. & Choudhary G. (2003) A compilation of infrared absorption spectra of some specific gemstones – as an aid to their identification. Australian Gemmologist, 21, 321-327