ABOUT ME
– I design bespoke gemological experiences –
My name is Laurent Massi — a passion-driven independent gemologist. As a professor of gemology, gemstones expert, speaker and blogger, I have accumulated over 18 years’ hands-on experience of teaching and lecturing on gemstones at all levels, both within the Gems and Jewelry industry, and beyond.
“My mission is to help you built a strong gemological knowledge through bespoke education tailored to your needs”
While I am engaged in multiple gemstone-related activities, I have a single mission: dedicating my career to the advancement and the dissemination of gemological knowledge by designing bespoke gemological experiences for the trade and the public alike.
In other words, I am obsessed with sharing my passion for common and uncommon gemstones with as many like-minded people as possible.
Through customized educational content, training, conferences, workshops and educational field-trips, I deliver unique and bespoke gemological experiences to my clients.

Having previously managed both a gem laboratory and a gem school, as well as traveling extensively to gemstone mining and trading areas all around the world, I have over time developed a unique set of knowledge, skills and a teaching method that makes me uniquely suited to ensuring the success of my clients by helping them grow their gemological knowledge and skills, whatever the level they are starting from or the level of knowledge they plan to achieve.
During the past two decades, I have been fortunate to work with some prestigious clients, including: Asian Institute of Gemological Sciences (AIGS), Gemological Institute of America (GIA), Gemfields, Van Cleef & Arpels, Cartier, Christian Dior, Chow Tai Fook, Christie’s, Louis Vuitton, Laboratoire Français de Gemmologie (LFG), Association Française de Gemmologie (AFG), Association progrès du management (APM), Institut National de Gemmologie (ING), The Montreal School of Gemmology (EGM), Alliance française de Bangkok, Givaudan, Culture Secrets, French Tech Thailand, Musée de Minéralogie MINES ParisTech, Musée des Minéraux de L’Université Pierre et Marie Curie (UPMC).
“I have developed a unique methodology that ensures an optimum learning experience for my clients“
In my spare time, I run a gems- & gemology-centric bilingual blog in both English (named “Through the Eyes of a Gemologist”) and in French (named “Sous l’Oeil du Gemmologue”) in which I share all things I like about gems and gemology as well as some of the truly exceptional gems and jewelry pieces I encounter in my activities or during my educational field-trips.
I also experiment with pictures of gemstone inclusions through a photomicrography activity. As a “serial spinel lover” and roughologist, I have created a private group on Facebook named Spinelover – Spinel Lover – that now has more than 1000 members, all passionate about this amazing gemstone (crystal, rough or polished).
If you would like to discuss a project or a collaboration, I would love to hear from you. Click on the following link to get in touch.
You can also find me on Linkedin, Instagram & Facebook, get my peer-reviewed articles on ResearchGate as well as read articles on uncommon colored stones, unique diamonds, gemology and jewelry on my blog (ici en Français).
THE PAST
I started to teach gemology more than 18 years ago in Paris at ING, the French National Institute of Gemology, whilst I was at the same time studying chemistry and physics at university.
After finishing my PhD in Materials Science on natural diamonds, I relocated to Bangkok, Thailand where I became the new Director of AIGS, an international gemological laboratory. After a few years, my passion for teaching led me to embrace the challenge of reopening and directing the prestigious GIA Thailand Campus, a gemological school also based in Bangkok.
The following is a list of the positions I have held:
AIGS SCHOOL
Asian Institute of Gemological Sciences, Bangkok – Thailand
2015 – 2016 | Director of Global Education
GIA
Gemological Institute of America, GIA Thailand Campus
2011 – 2013 | Director
LMTC
Laurent Massi Training & Consulting
2010 – 2011 | Gemological Consultant
AIGS LAB
AIGS Gemstone Identification, Grading & Research Laboratory, Bangkok – Thailand
2007 – 2010 | Director
AIGS SCHOOL
AIGS Gemological School, Bangkok – Thailand
2007 & 2010 | Director of Academics
ING
Institut National de Gemmologie, Paris – France
2000 – 2005 | Gem Educator
IMN
Institut des Matériaux de Nantes, Nantes – France
2003 – 2006 | Doctoral Student
SELECTED PUBLICATIONS
I have written and co-written articles on many different gemstones, from diamonds, rubies and sapphires to extremely rare gems, such as Hibonite and Taaffeite. Those articles have been published in magazines and peer-reviewed journals such as “Diamond & Related Materials”, the “Journal of Applied Spectroscopy”, “Gems & Gemology”, a quarterly scientific journal published by GIA and “InColor magazine”, ICA’s (International Colored Gemstone Association) quarterly publication, among others.
The following is a list of some of the gemological articles I have written and co-written (with a direct link to the publication when available):
– Pardieu V., Sangsawong S., Muyal J., Chauviré B., Massi L., Sturman N. (2013) “Rubies from the Montepuez Area (Mozambique)”, GIA Thailand Research , GIA New From Research, 84 pages [GIA link].
– Hainschwang T., Fritsch E., Massi L., Rondeau B., Notari F. (2012) “The C center isolated nitrogen-related infrared absorption at 2688 cm-1: perfect harmony in diamond”, Journal of Applied Spectroscopy, vol. 79, No. 5, pp. 737 – 743 [Springer link].
– Renfro N., Massi L. (2012) “Red Taaffeite Crystal”, Gems and Gemology, vol. 48, No.3, p. 214 [GIA link].
– Hainschwang T., Notari F., Massi L., Armbruster T., Rondeau B., Fritsch E., Nagashima M. (2010) Hibonite: a new gem mineral, Gems and Gemology, vol. 46, No. 2, pp. 135 – 138 [GIA link].
– Hainschwang T., Notari F., Fritsch E., Massi L., Rondeau B., Breeding C.M., Vollstaedt H. (2008) “HPHT treatment of CO2 containing and CO2-related brown diamonds”, Diamond and Related Materials, vol. 17, pp. 340 – 351 [ScienceDirect link].
– Massi L. (2007) AIGS Bangkok inspects an exceptional clinohumite from Tajikistan, I.C.A. InColor Magazine, Summer 2007, pp. 30 – 31 [ICA link].
– Massi L. (2007) Color-change bastnäsite-(Ce) from Pakistan, Gems and Gemology, vol. 43, No.2, pp. 165 – 166 [GIA link].
– Fritsch E., Hainschwang T., Massi L., Rondeau B. (2007) Hydrogen-Related Optical Centers in Natural Diamond: An Update, New Diamond and Frontier Carbon Technology, vol. 17, No. 2, pp. 63 – 89 [ResearchGate link].
– Fritsch E., Massi L., Rossman G.R., Hainschwang T., Jobic S., Dessapt R. (2007) Thermochromic and photochromic behaviour of “chameleon” diamonds, Diamond and Related Materials, vol. 16, pp. 401 – 408 [ScienceDirect link].
– Massi L. (2006) Studies of defects in brown and hydrogen-rich diamonds, PhD thesis, University of Nantes – France, 372 pages [PDF link].
– Hainschwang T., Notari F., Fritsch E., Massi L. (2006) “Natural, untreated diamonds showing the A, B and C infrared absorptions (“ABC diamond”) and the H2 absorption“, Diamond and Related Materials, vol. 15, pp. 1555 – 1564 [ResearchGate link].
– Massi L., Fritsch E., Collins A.T., Hainschwang T., Notari F. (2005) “The ‘amber centres’ and their relation to the brown color in diamond”, Diamond and Related Materials, vol. 14, pp. 1623 – 1629 [ScienceDirect link].
– Massi L. « Les corindons à changement de couleur » [in French] “Color change corundum” (2005) Revue Française de Gemmologie AFG, No. 152, pp. 16 – 19 [AFG link].
– Massi L., Fritsch E. « les corindons diffusés » [in French] “The diffusion treatment of corundum” (1999) Revue Française de Gemmologie AFG, No. 152, pp. 16 – 19 [AFG link].
Selected Conferences
I have made presentations and spoken extensively about gems and jewelry as a speaker at conferences in more than 15 countries across the world. My audiences have included attendees of all gemological levels, from beginners to top level gemologists and scientists.
The following is a list of some of my gemological talks:
– Massi L. (2017) « De la mine à la Place Vendôme: Itinéraire d’une gemme » [in French] “From the mine to the Place Vendôme: the path of a gem”, CultureSecrets & Université MINES ParisTech – Musée de Minéralogie, Paris, France.
– Massi L. (2017) « Nouvelles sources de rubis: impacts et conséquences ? » [in French] “New ruby sources: impacts and consequences ?”, Université Pierre & Marie Curie – Musée de Minéralogie, Paris, France.
– Massi L. (2017) “New major ruby sources from East-Africa: How those discoveries have deeply impacted the ruby industry ?“, Instituto Gemológico Español (IGE) & World Gem Foundation (WGF), Madrid, Spain.
– Massi L., Jacquin T. (2017) “JewelTech: How 3D printing has revolutionized the jewelry industry ?“, Les Mercredis de la French Tech #24: 3D & IMAGERY TECH: Disruption Of An Old World, The Hive Bangkok, Bangkok, Thailand.
– Massi L. (2016) « Introduction à la Gemmologie, l’Art et la Science des Pierres Précieuses » [in French] “Introduction to Gemology, the Art and Science of Gemstones”, Tous Experts – Association Progrès du Management APM, Sofitel Bangkok Sukhumvit, Bangkok, Thailand.
– Massi L. (2016) “Phenomenal Gems”, 57th Bangkok Gems and Jewelry Fair, Impact Challenger, Bangkok, Thailand
– Massi L. (2015) “From Mines to Markets: the Dawn of a New Era in the Global Ruby Market”, 56th Bangkok Gems and Jewelry Fair, Impact Challenger, Bangkok, Thailand.
– Massi L. (2015) “New Challenges in Teaching Gemology in the 21st Century”, Malaysia International Jewellery Fair, KLCC, Kuala Lumpur, Malaysia
– Massi L. (2015) « Le marché du rubis au 21e siècle: évolution ou révolution ? » [in French], 14th Rendez-Vous Gemmologiques de Paris – Association Française de Gemmologie (AFG), Paris, France.
– Massi L. (2015) “From Mines to Final Customers: the Dawn of a New Era in the Global Ruby Market”, Gemfields & Fabergé, London, England.
– Massi L. (2014) “From Mines to Final Customers: the Dawn of a New Era in the Global Ruby Market”, 24th Facets Sri Lanka Gem Show, BMICH, Colombo, Sri Lanka.
– Massi L. (2013) « Rubis : de l’Afrique à l’Asie : Nouvelles Sources – Nouveaux Défis » [in French] “Rubies: From Africa to Asia: New Sources – New Challenges”, Dior Joaillerie, Paris, France.
– Massi L. (2013) « Rubis : de l’Afrique à l’Asie : Nouvelles Sources – Nouveaux Défis » [in French], “Rubies: From Africa to Asia: New Sources – New Challenges”, Institut National de Gemmologie (ING), Paris, France.
– Massi L. (2013) « Introduction à la Gemmologie » [in French], “Introduction to Gemology”, Institut Français de la Mode (IFM), Paris, France.
– Massi L. (2013) « Rubis : de l’Afrique à l’Asie : Nouvelles Sources – Nouveaux Défis » [in French] “Rubies: From Africa to Asia: New Sources – New Challenges”, Sotheby’s Paris, Paris, France.
– Massi L. (2013) « Introduction à la Gemmologie » [in French] “Introdcution to Gemology”, University Paris-Est – Marne-la-Vallée, Master Innovation Design et Luxe, Marne-la-Vallée, France.
– Massi L. (2013) « Rubis : de l’Afrique à l’Asie : Nouvelles Sources – Nouveaux Défis » [in French] “Rubies: From Africa to Asia: New Sources – New Challenges”, Laboratoire Français de Gemmologie (LFG) – Union Française de la Bijouterie, Joaillerie, Orfèvrerie et du négoce en Pierres et Perles (UFBJOP), 6eme Conférence du Laboratoire Français de Gemmologie, Paris, France.
– Massi L. (2013) “Mozambique: the New Major Source for Rubies – How this discovery has impacted the entire Ruby Trading?”, Malaysia International Jewellery Fair, KLCC, Kuala Lumpur, Malaysia.
– Massi L. (2013) “Thailand: Gemstones Heaven”, Alliance Française de Bangkok, Bangkok, Thailand.
– Massi L. (2013) “Gemstones from Madagascar: Ruby and Sapphire Mines”, Madagascar’s Beauty and Business Opportunities conference, Center for Diplomatic and Strategic Studies (CEDS), Silom Holiday Inn, Bangkok, Thailand.
– Massi L. (2013) « Thaïlande : Terre de Gemmes – Introduction à la Gemmologie » [in French], “Thailand – Gemstones Heaven – Introduction to Gemology”, Alliance Française de Bangkok, Bangkok, Thailand.
– Massi L. (2013) “Ruby and Sapphire: from Mine to Yours”, CLSA ASEAN Forum 2013, Grand Hyatt Erawan, Bangkok, Thailand.
– Massi L. (2012) “Phenomenal Gemstone Phenomena”, 55th GIA Gems Gathering, Bangkok Crowned Plaza Lumpini, Bangkok, Thailand.
– Massi L. (2012) “Pearls and the GIA Description System”, Malaysia International Jewellery Fair, KLCC, Kuala Lumpur, Malaysia.
– Massi L. (2011) “How new ruby deposits and innovative treatments are influencing the industry”, Gemological Institute of America (GIA), Carlsbad, California, USA.
– Massi L. (2010) “Thailand: latest update on corundum treatments”, 15th years of Ecole de Gemmologie de Montreal / the Canadian Gemmological Association Congress, Faculty Club, McGill University Club, Montreal, Canada.
– Massi L. (2010) “Gemology: where Science and Art meet”, Silpakorn University, Nakhon Pathom, Bangkok, Thailand.
– Massi L. (2009) “Latest observations made in AIGS Gem Laboratory on corundum treatments, mainly focus on Pb treatments”, DOJI Laboratory for Gemology and Jewelry Conference, DOJI Gold & Gems Group, Hanoi, Vietnam.
– Massi L. (2009) « Bangkok : situation du marché – nouveaux traitements » [in French] “Bangkok : Gem market and new treatments”, 10th Rendez-Vous Gemmologiques de Paris – Association Française de Gemmologie (AFG).
– Massi L. (2009) “Latest observations made in AIGS Gem Laboratory on corundum treatments, mainly focus on Pb treatments”, 2009 Taipei Gemological Symposium, Republic of China Gemological Association, Taipei, Taiwan.
– Massi L. (2009) « Bangkok : situation du marché – nouveaux traitements » [in French] “Bangkok : Gem Market and New Treatments”, 10th Rendez-Vous Gemmologiques de Paris – Association Française de Gemmologie (AFG).
– Massi L. (2009) “Origin of the alexandrite effect in color changing corundum”, 2nd International Gem & Jewelry Conference (GIT 2008), December 11-14, 2008, Bangkok and Kanchanaburi, Thailand.
– Hainschwang T., Notari F., Fritsch E., Massi L., Rondeau B., Breeding C.M., Vollstaedt H. (2008) “Traaitementa HPHT des diamants bruns contenant du CO2 et des diamants apparentés aux diamants CO2”, 22ème réunion des Sciences de la Terre, Nancy, France.
– Notari F., Hainschwang T., Fritsch E., Massi L., Breeding C.M., Rondeau B., Grobon-Caplan C. (2008) “Les caractéristiques spectrales IRTF des diamants dits riches en CO2 sont-elles représentatives de la pression de formation?”, 22ème réunion des Sciences de la Terre, Nancy, France .
– Massi L. (2007) “How Gemological Laboratories may help you to increase buyer confidence?”, 40th Bangkok Gems and Jewellery Fair, Impact Challenger, Bangkok, Thailand.
– Massi L. (2007) “From Star to Chameleon: a review of phenomenal gemstones”, 39th Bangkok Gems and Jewellery Fair, Impact Challenger, Bangkok, Thailand.
– Massi L. (2006) « Les gemmes à effet Usambara» [in French] “Usambara effect in gemstone”, 7th Rendez-Vous Gemmologiques de Paris – Association Française de Gemmologie (AFG), Paris, France.
– Massi L, Fritsch E., Rossman G.R., Hainschwang T., Jobic S., and Dessapt R. (2006) “Chameleon Diamonds: A Proposed Model to Explain Thermochromic and Photochromic Behaviors”, 4th International Gemological Symposium – 1st GIA Gemological Research Conference, San Diego, California, USA.
– Hainschwang T., Notari F., Fritsch E., Massi L., Breeding C.M., Rondeau B. (2006) “Natural “CO2-rich” colored diamonds”, 4th International Gemological Symposium – 1st GIA Gemological Research Conference, San Diego, California, USA.
– Fritsch E., Massi L., Hainschwang T., Notari F. (2005) “A proposed classification of brown diamonds”, Diamond 2005 – 16th European Conference on Diamond, Diamond-like Materials, Carbon Nanotubes, Nitrides & Silicon Carbide, Toulouse, France (Poster).
– Fritsch E., Massi L., Hainschwang T., Notari F. (2005) “A preliminary classification of brown diamonds”, De Beers Diamond Conference, Oxford, United Kingdom (Poster).
– Massi L., Fritsch E., Hainschwang T., Notari F. (2005) “Studies of atomic-scale defects in brown and hydrogen-rich diamonds”, PhD student’s day 2005 – ED STIM, Ecole Centrale de Nantes, Nantes – France.
– Massi L. (2005) « Les corindons à changement de couleur » [in French] “Color change corundum”, 6th Rendez-Vous Gemmologiques de Paris – Association Française de Gemmologie (AFG), Paris, France.
– Massi L.. Piat E. (2004) « Les nouvelles couleurs des saphirs – le traitement des corindons au béryllium » [in French] “New colors of sapphires: the beryllium treatment”, Bijorhca Jewellery Show, Paris, France.
– Fritsch E., Rondeau B., Notari F., Massi L. (2004) “Hydrogen-rich diamonds: a fresh look through old samples”, De Beers Diamond Conference, Warwick, United Kingdom (Poster).
– Massi L., Fritsch E., Hainschwang T., Notari F (2004) “Brown diamonds: what’s in a name”, Diamond 2004 – 15th European Conference on Diamond, Diamond-like Materials, Carbon Nanotubes, Nitrides & Silicon Carbide – Riva del Garda, Trentino, Italy (Poster).
– Massi L. (2004) « Les gemmes à changement de couleur » [in French] “Color change gemstones”, Gemmological Research Center (CRG) Jean-Pierre Chenet – University of Nantes, Nantes, France.
– Massi L., Fritsch E. (2004) « L’effet alexandrite et les gemmes à changement de couleur » [in French] “The alexandrite effect and color change gemstones”, Groupe De Recherches CNRS “Color and visual effects of materials” – L.O.S. – University of Pierre et Marie Curie, Paris, France.
– Massi L., Fritsch E. (2000) « Les corindons diffusés » [in French] “The diffusion treatment of corundum”, 3th Rendez-Vous Gemmologiques de Paris – Association Française de Gemmologie (AFG), Paris, France.