37th IGC 2023 Tokyo, Japan

23. Oct 27. Oct. 2023

IGC 2023: Tokyo, Japan

After having had to postpone IGC twice, IGC 2023 took place in Tokyo from October 23-27 2023.

We, the members of IGC Japan Organizing Committee were pleased and delighted to welcome you to the 37th International Gemmological Conference, (IGC 2023 Japan) which was held in October 2023 at the prestigious National Museum of Nature and Science, Tokyo, Japan.


National Museum of Nature and Science
Tokyo (Japan)

Monday 23rd October

Location: Ueno Seiyoken Hall

9:00 - 10:00 Registration

10:00 - 10:30 IGC Opening words (JJA, JGS, GSJ, IGC Executive Secretary)

10:30 - 17:00 Open Colloquium

10:30 - 11:00 Jayshree Panjikar: Past, present and the future of IGC

11:00 - 11:30 Hanco Zwaan: Diamonds and synthetic diamonds

11:30 - 12:00 Hisao Kanda: A brief history of synthetic diamond researches in Japan

12:20 - 14:00 Lunch party

14:30 - 15:00 Pornsawat Wathanakul: The Importance of Research for Gem & Jewellery Industry

15:00 - 15:30 Yuichi Nakamura: Initiatives for sustainable pearl cultivation in Japan

15:30 - 16:00 Michael Krzemnicki: Colour varieties of gems – where to set the boundary?

16:00 - 16:30 Communication

16:30 - 17:00 Group photo at the front of National Museum of Nature and Science

17:30 - 18:30 IGC Executive Committee Meeting No.1

18:00 - 20:30 Reception & Buffet at the rooftop of National Museum of Nature and Science

Tuesday 24th October

Location: National Museum of Nature and Science, Conference Hall

8:00 - 9:00 Setting and registration

Opening ceremony

9:00 - 9:20 Daily schedule annoncement

Session 1: Diamonds, Chairperson: Emmanuel Fritsch

9:20 - 9:40 Robert Coenraads: Mapping underground rivers at the Copeton Diamond Field, New South Wales, Australia Following these ‘deep leads’ to further riches

9:40 - 10:00 Thomas Hainschwang: Violet Diamonds from Argyle: New Insights into the Cause of their Unique Color

10:00 - 10:20 Suzanne van Leeuwen, J. C. (Hanco) Zwaan: The Banjarmasin Diamond in Amsterdam -War Booty from Borneo

10:20 - 10:50 Coffee break

10:50 - 11:10 Hiroshi Kitawaki, Kentaro Emori, Mio Hisanaga, Masahiro Yamamoto, Makoto Okano, Zhenghao Zhao, Jayam Sonani, Hiroyuki Harada: Gemmological studies of “Hybrid Diamond” (Natural + CVD synthetics)

11:10 - 11:30 Michael Mintrone, Luc Phan, Jean-Pierre Chalain: A study of nickel-bearing type Ia diamonds

11:30 - 11:50 Sergey Sivovolenko, Roman Serov: CVD Rough Diamonds Striae Grading Approach based on Deviated Optical Performance of Polished CVD Diamonds

11:50 - 13:20 Lunch

12:00 - 13:00 IGC Executive Committee Meeting No.2

Session 2: History and Museums, Chairperson: Jayshree Panjikar

13:20 - 13:40 Koichi Momma, Ritsuro Miyawaki: Overview of the “GEM” special exhibition at the NMNS

13:40 - 14:00 Ahmadjan Abduryim: A study of Chikayama’s gem and mineral collections and building a gem museum

14:00 - 14:20 Stefanos Karampelas, Eloïse Gaillou, Ugo Hennebois, Farida Maouche, Annabelle Herreweghe, Bérengère Meslin Sainte Beuve, Didier Nectoux, Aurélien Delaunay: Study of a historical Alexandrite from Paris school of mines collection

14:20 - 14:40 Stephen Kennedy, Mary Montagu-Scott, Susan Tomkins: Snapshot of rubies from 1915

14:40 -15:00 Michael Hügi: Quartz crystals from alpine fissures: their formation and the historical significance of alpine quartz as raw material for objets d’art

15:00 - 15:30 Coffee break

Session 3: Gemmology 1, Chairperson: Tay Thye Sun

15:30 - 15:50 Maxence Vigier, Emmanuel Fritsch, Theo Cavignac, Camille Latouche, Stephane Jobic: Blue shortwave luminescence of gems the role of titanate groups

15:50 - 16:10 Miro Ng: Proposed New Filler Type for Emerald Fracture Filling: Design, Detection, Differentiation, Disclosure

16:10 - 16:30 Javier Garcia-Toloza, Holman Alvarado, Carlos Julio Cedeño, Camilo Betancourt: Fingerprint differences between Emeralds from two main zones of production in Colombia in response to input from their host rock

16:30 - 17:00 Coffee break

Session 4: Gemmology 2, Chairperson: Wilawan Atichat

17:00 - 17:20 Lore Kiefert, Michael Krzemnicki, Jeanette Fiedler, T. Sintayehu, Masaki Furuya: Purple to bluish grey chalcedony from Ethiopia

17:20 - 17:40 Karen Fox, Andrew McDonald: Rose Quartz: Journey Into the Nano-Jungle

17:40 - 18:00 Boris Chauviré, Jean-Yves Mevellec, Jacques Ferreire, Paul Thomas, Emmanuel Fritsch: Opal stability: a step toward detection

18:30 - 20:30 Dinner at Museum Restaurant

Wednesday 25th October

Location: National Museum of Nature and Science, Conference Hall

Session 5: Colored stones 1, Chairperson: Ahmadjan Abduriyim

9:00 - 9:20 Nathan Renfro: Microfeatures of Beryl Group Gems including the Newest Mineral Variety, Johnkoivulaite

9:20 - 9:40 Gagan Choudhary: New yellow to grey-brown opals from Australia

9:40 - 10:00 Anette Juul-Nielsen, Arent Heilmann: A nuummite occurrence from kangerluarsuk in the Maniitsoq Region, West Greenland

10:00 -10:20 Claudio Milisenda, Stefan Müller: Colour change Paraiba tourmaline from Brazil

10:20 - 10:50 Coffee break

Session 6: Colored stones 2, Chairperson: Shane Mcclure

10:50 - 11:10 Seung Kwon Lee, Dongwook Shin: Sulfur-based species induced photochromism in sodalite

11:10 - 11:30 Jayshree Panjikar, Aatish Panjikar: Study and investigation of garnet from Balangir in Odisha, India

11:30 - 11:50 Bihan Lin, Xingtong Li, Longbo Zhang, Xiaojing Lai, Qian Zhang: Gemological and Luminescence Characteristics of Taaffeites from Mogok, Myanmar

11:50 - 12:10 Bahareh Shirdam, Yang Mingxing, Andy Shen, Nader Taghipour, Soheila Aslani: Investigating the Provenance signature of Tourmaline-Bearing Turquoise in the Kuh Zar Gold Deposit, Semnan Province, Iran

12:10 - 13:40 Lunch

Session 7: Colored stones 3, Chairperson: Stefanos Karampelas

13:40 - 14:00 Masaki Furuya: Cobalt spinel from Bai Buoi mine,Yen Bai, Vietnam

14:00 - 14:20 Chengsi Wang, Jiling Zhou, Andy Shen: Quantitative estimation of spinel’s thermal and geothermal history by photoluminescence spectroscopy and its application in spinel origin determination

14:20 - 14:40 Qingchao Zhou, Chengsi Wang, Andy Shen: Mechanism and Application of High-Temperature Copper Diffusion in Surface Recoloring of Labradorites

14:40 - 15:00 Brendan Laurs: A Review and Synthesis of the Geology and Gem Resources of Granitic Pegmatites in Southern California, USA

15:00 - 15:30 Coffee break

Session 8: Technology & Techniques, Chairperson: Brendan Laurs

15:30 - 15:50 Michael Krzemnicki, Pierre Lefèvre, Wei Zhou: Phase transformations as important markers for heat treatment detection in corundum and other gemstones

15h50 - 16:10 Tasnara Sripoonjan, Bhuwadol Wanthanachaisaeng: Applications of Python for Spectroscopic Data Processing, Analysis and Machine Learning Modeling in Gemmology

16:10 - 16:30 Hao Wang, Dirk Weltz, Michael S. Krzemnicki, Andreas Mack, Markus Wälle: Effects of Gamma Irradiation on Ruby and Pink Sapphire and Potential Detection. Methods in Gem Labs

16:30 - 16:50 Tom Stephan, Vladimir Hutanu, Xiaosong Li, Thomas Lind, Stefan Müller: Irradiation treatment and gamma-spectroscopy of morganite

16:50 - 17:10 Montira Seneewong-Na-Ayutthaya, Bhuwadol Wanthanachaisaeng, Waratchanok Suwanmanee, Thanapong Lhuaamporn, Pimlapat Kamkeaw, Sarun Phibanchon Tasnara Sripoonjan, and Thanong Leelawatanasuk: An implementation of machine learning in ruby and sapphire origin determination

Free evening

Thursday 26th October

Location: National Museum of Nature and Science, Conference Hall

Session 9: Corundum 1, Chairperson: Claudio Milisenda

9:00 - 9:20 U. Atikarnsakul, W.Soonthorntantikul, Sudarat Saeseaw: Color enhancement in yellow sapphire

9:20 - 9:40 Aaron Palke, Shane McClure, Nathan Renfro: Unstable Color in Padparadscha

9:40 - 10:00 Seika Oto, Akira Miyake, Yohei Igami, Kentaro Emori, Hiroshi Kitawaki: Crystal structure of nano inclusions in blue sapphire from Diego Suarez, Northern Madagascar

10:00 -10:20 Waratchanok Suwanmanee, Chotika Kittikunlayaworakun, Thanapong Lhuaamporn, Chanenkant Jakkawanvibul, Thanong Leelawatanasuk, Wilawan Atichat, Visut Pisutha-Arnond, Nongnuch Jangsawang, Kanwalee Pangza: Influence of Irradiation on Colour Modification and Colour Stability of Rubies: A Preliminary Study

10:20 - 10:50 Coffee break

Session 10: Corundum 2, Chairperson: Michael Krzemnicki

10:50 - 11:10 E. Billie Hughes, Wim Vertriest: Low Temperature Heat Treatment of Burmese Ruby

11:10 - 11:30 Bovon Ubolchay, Chakkaphan Sutthirat, Bhuwadol Wanthanachaisaeng, Gamini Zoysa, Waratchanok Suwanmanee, Arūnas Kleišmantas: Milky appearance of Geuda sapphire from Sri Lanka

11:30 - 11:50 Wiwat Wongkokua, Thanapong Lhuaamporn, Natthapong Monarumit, Phongsakorn Kajornboonsook, Pornsawat Wathanakul: Explanation on Yellow, Green and Brown Coloration Series of Basalt Related Bangkaja Sapphires

11:50 - 12:10 Walter Balmer: FTIR Fingerprinting: a case study on mineral inclusion identification by FTIR applied on rubies from marble-hosted deposits

12:10 - 13:00 Lunch

12:10 - 13:00 IGC Executive Committee Meeting No.3 move to Jadeite Museum

13:00 - 15:00 Visit of Hisui Genseki-Kan (Jadeite Museum) move to National Museum of Nature and Science

15:30 - 18:00 Visit of Tokyo National Museum of Nature and Science

18:00 - 18:40 Move to Symphony Cruise Terminal

19:00 - 21:00 Gala Dinner

Friday 27th October

Location: National Museum of Nature and Science, Conference Hall

Session 11: Pearls and amber, Chairperson: Pornsawat Wathanakul

9:00 - 9:20 Tay Thye Sun, Michael Krzemnicki, Gina Brombach, Thet Tin Nyunt, Myo Lwin, Tay Zar Linn, Loke Hui Ying: Analysis of Myanmar golden-lipped cultured pearls using X-ray radiography, EDXRF, UV-Vis-NIR and Raman spectroscopy

9:20 - 9:40 Laurent Cartier, Michael Krzemnicki, Bertalan Lendvay, Nadja Morf, Joana B. Meyer: DNA Fingerprinting and age dating of historic natural pearls: a combined approach

9:40 - 10:00 Sutas Singbamroong, Mohamed Karam, Nazar Ahmed, Nahla AlMuheiri, Thanong Leelawattanasuk, Bhuwadol Wanthanachaisaeng, Jirapit Jakkawanvibul: Nacreous Blister Pearl Discovered in Edible Oyster (Crassostrea gigas)

10:00 -10:20 A. Costanzo, B. Bojarski, M. Kosior, A. Klikowicz-Kosior: Baltic amber and its inclusions: an insight into the origin and nature of the trapped material

10:20 - 10:40 Yan Li, Minghan Peng, Yamei Wang: Effects of weathering on FTIR spectra and origin traceability of archaeological amber: The case of the Han Tomb of Haihun Marquis, China

10:40 - 11:10 Coffee break

Session 12: Jade, Chairperson: Andy Hsitien Shen

11:10 - 11:30 Supparat Promwongnan, Wilawan Atichat, Kannatee Fueangaksorn, Visut Pisutha-Arnond, Thanong Leelawatanasuk: Treated jadeite-jade: Unusually bright fancy colours

11:30 - 11:50 Elizabeth Su: Origin Identification Characteristics of High-quality Green Jadeite

11:50 - 12:10 Shang-I (Edward) Liu, Ka-Yi (Angela) Man, Montira Seneewong-Na-Ayutthaya, Chanenkant Jakkawanvibul: Geographic Origin Determination of Fei Cui: A comparison of high-quality green Fei Cui from Myanmar, Guatemala, and Italy

12:10 - 13:30 Lunch

13:30 - 14:00 IGC Business Meeting

Closing ceremony

14:00 - 15:30 IGC plenary meeting & closing ceremony

16:00 - 19:00 Move to Xiv Lake Yamanaka, Mount Fuji area

Pre-conference excursion

Itoigawa Jadeite Excursion
20-22 October 2023

Discover the premier Japanese gem and the official national stone – Itoigawa Jadeite sourced from Niigata prefecture. Immerse yourself in the experience of beholding, touching, and sensing the grandeur of the largest jadeite boulder, weighing an impressive 102 tons. Embark on a journey to explore the two significant jadeite sources in Itoigawa and Omi regions, uncover your own jadeite treasures at the jadeite beach, and delve into the Earth’s mysteries at the “Fossa Magna Museum,” situated in the UNESCO Global Geopark.

Post-conference excursion

Pearl Excursion
29-31 October 2023

Visit a beautiful island-Mikimoto Island in Mie Prefecture. It is the first place where was the successfully cultured the Akoya pearl by Kokichi Mikimoto. The research institute of Akoya pearl in Ise city of Mie prefecture was open for IGC members to see and discuss their advanced research results and techniques. After visiting of pearl farm, travel to the Japan’s old capital and emperor’s residence, Kyoto city, to learn more about traditional Japanese culture, the temples, shrines and other fascinating areas.