Thanks and disclaimer:


Important Note: The author: Vincent Pardieu is an employee of GIA (Gemological Institute of America) Laboratory Bangkok since Dec 2008. Any views expressed on this website - and in particular any views expressed by Vincent Pardieu - are the authors' opinions and do not necessarily reflect the opinions of GIA or GIA Laboratory Bangkok . GIA takes no responsibility and assumes no liability for any content on this website nor is GIA liable for any mistakes or omissions you may encounter. GIA is in particular not screening, editing or monitoring the content on this website and has no possibility to remove, screen or edit any content.


About FieldGemology. org

This website is home for "Shameless Travel Addicted Gemologist" Vincent Pardieu (B.Sc., GGA, G.G.). Vincent is "Supervisor, Field Gemology" at GIA Laboratory Bangkok. He is a gemologist specialized on "origin determination of gemstones".
This is also home for Vincent's regular traveling companions: David Bright, Jean Baptiste Senoble, Richard W. Hughes, Guillaume Soubiraa, Walter Balmer, Michael Rogers, Kham Vannaxay and many others like recently: Philippe Ressigeac, Oliver Segura , Flavie Isatelle and Lou Pierre Bryl.

We are gemologists (gemmologists) sharing a passion for gemstones, gemolology (gemmology), gem people and traveling.

You will find in this website gemological expedition reports and some studies of gemological interest.

Visiting many gem mining areas we saw that people in remote mining and trading areas have difficulties to access to gemological publications. As today the Internet can be accessed in most of these gem mining areas and trading centers, the author started to build this website to give gem people living there the opportunity to see the result of the gemological expeditions they were associated in. It is a way to thanks them for their time and collaboration and to help them to get access to more gemological information.

At the same time the author hope that these expedition reports will please the people from consuming countries interested in gemstones and fascinated by their mysterious origins. Our purpose here is to help people facing difficulties to get quality first hand information about gems and their origins to get the information they need through this website and its links.

With our field expeditions to gemstone mines and gem markets around the world, we intend also here to share our passion for photography, gems and our fascination for the work of the "Gem People" bringing gemstones from the ground to magnificent jewelry.

From the gems external beauty to the intimate beauty of gemstone inclusions, from gem lore to the mines, the people and the landscapes gems origin from, we expect to share with you our passion for gemstone beauty.

We also invite you to join us on some gemological forums we are active in as they are convenient tools to get rapid answers to your questions as they are regularly visited by many other passionate gemologists, jewelers, hobbyists and professionals willing to learn more and share their knowledge about gemstones.


Website Map


Index page: Vincent Pardieu's Blog

About the Author

About me : How did a countryside Frenchman became a "Shameless travel addicted gemologist"? ( Under construction)


Contact the author:


Write Comments:

Fieldgemology Page on facebook

Popular Articles

"Tsavorite, an Untamed Gem" with R.W.Hughes, first published in ICA's InColor (Winter 2008)
"Working the blue seam" The Tanzanite mines of Merelani with R.W.Hughes first published on
"Spinel, the resurection of a Classic" with R.W. Hughes, first published in ICA's InColor (Summer 2008)

Gemological studies

(Apr. 2009) "Sapphires reportedly from Batakundi / Basil area" a preliminary study about unusual sapphires we saw at GIA Laboratory Bangkok
(Mar. 2009) "Rubies from Niassa province, Mozambique" a preliminary study about rubies we saw at GIA Laboratory Bangkok
"Lead glass filled rubies" :
First published on AIGS Lab Website (Feb 2005)

Expedition Reports

Autumn. 2009: GIA Field Expedition FE09: Rubies from Mozambique. (pdf file)

May. 2009: GIA Field Expedition FE08: Melos and their pearls in Vietnam. (pdf file)

Dec. 2008 and Feb-Mar. 2009: GIA Field Expeditions FE01 and FE04: Rubies and sapphires from Pailin, Cambodia. (pdf file)

Aug. 2008: Sapphires and Tsavorite from the south of Madagascar with the AFG (Association francaise de Gemmologie) : Available soon...

Apr. 2008: Expedition to the new Winza ruby deposit in central Tanzania with Jean Baptiste Senoble and the support of the Gubelin Gem Lab

October 2007: Gemological expedition to East Africa (Kenya and Tanzania) with Richard W. Hughes, Mike Rogers, Guillaume Soubiraa, Warne and Monty Chitty and Philippe Bruno:

Summer 2006: Expeditions to Central Asia gem wealth with Guillaume Soubiraa and the support of the AIGS, the ICA and the Gubelin Gem Lab:

Oct. 2005: Colombia by J.B. Senoble

Sep. 2005: Madagascar with Richard W. Hughes and Dana Schorr (Will be available one of these days...)

Summer 2005: Gemological expeditions to South East Asia (Vietnam) South Asia (Sri Lanka) and East Africa (Kenya, Madagascar and Tanzania) with J.B. Senoble and Tanguy Lagache with the support of the AIGS, the ICA and the Gubelin Gem Lab:

- Feb. 2005: A visit to Thailand, Cambodia with the AFG (Association Francaise de Gemmologie) (under construction)

- 2002-2007: Expeditions to Pailin (Cambodia), Chanthaburi Kanchanaburi (Thailand) Houay Xai (Laos) Mogok, Namya (Burma) (under construction)

- 2001: Expeditions to Namya, Hpakant and then Mogok with Ted and Angelo Themelis and Hemi Englisher (under construction)

Find our blogs using the following Keywords:

     black star sapphire
     Bo Rai
     Dak Nong
     Di Linh
     Fair Trade
     Field Report GIA
     Gemological study
     Ha Long
     Ha Long Bay
     Houay Xai
     Khao Ploy Waen
     Kho Laem Sing
     Kul I Lal
     lead glass filled ruby
     Luc Yen
     Mae Sot
     Mong Hsu
     pearl farm
     Phan Thiet
     Quy Chau
     Richard W. Hughes
     Richard Wise
     Sri Lanka
     star ruby
     Yen Bai

Find our photos using the following Keywords:

     Bai Lai
     Ha Long
     Ha Long Bay
     Luc Yen
     Minh Tien
     pearl farm
     star ruby
     Tan Huong
     Thac Ba

Discover fieldgemology newsletter:
(Currently under "hibernation status"...)

Number 01: Sept 2006
(I know: it was long time ago...)



THANKS for their support
for our field expeditions since 2005:


about gems, gemology, field expeditions, studying gemology, minerals, jade, pearls or jewelry?
We recommend these FORUMS
where the author is contributing:

Do you want to

Here are some recommended institutes where the author studied gemology in Thailand ... and was happy about his investment!

For those willing to go further after their gemological studies: Recommended Advanced Gemological Courses:

To finish here are some BOOKS about gemology
the author have read and appreciated and would like to recommend to people willing to learn more about gemstones, gemology and the places where gemstones are found:




Creative Commons License

The photos and articles on are licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 United States License.
Feel free to use the photos and articles with links and credits. No commercial use without permission.
All the best,

February 11th, 2012 | Keywords:emerald , Davdar , China Travel |
Blog Title: Davdar_Emeralds_Mineralogical_Magazine

Conditions for emerald formation at Davdar, China: fluid inclusion, trace element and stable isotope studies

Authors: D. Marshall, V. Pardieu, L. Loughrey, P. Jones and G. Xue.

Click here or on the photo to get the article

Abstract: Preliminary geological work on samples from Davdar in China indicate that emerald occurs in quartz veins hosted within upper greenschist grade Permian metasedimentary rocks including quartzite, marble, phyllite and schist. Fluid inclusion studies indicate highly saline fluids ranging from approximately 34 to 41 wt.% NaCl equivalent, with minimal amounts of CO2 estimated at a mole fraction of 0.003. Fluid inclusion, stable isotope and petrographic studies indicate the Davdar emeralds crystallized from highly saline brines in greenschist facies conditions at a temperature of ~350°C and a pressure of up to 160 MPa. The highly saline fluid inclusions in the emeralds, the trace-element chemistry and stable isotope signatures indicate that the Davdar emeralds have some similarities to the Khaltaro and Swat Valley emerald deposits in Pakistan, but they show the greatest similarity to neighbouring deposits at Panjshir in Afghanistan.

Keywords: beryl, China, Davdar, emerald, fluid inclusion study, greenshist facies, stable isotopes geochemistry

Read the rest of the article at the following link


Figure 1: Emerald crystals in matrix from Davdar mining area, Xin Jiang Province, China. The largest crystal is gem quality and about 5 centimeters long. Photo: V. Pardieu / GIA Laboratory Bangkok

This new article is based on the samples collected on site in China during the field expedition to the new Davdar emerald mining area lead by V. Pardieu in 2006 with the support of the AIGS and the Gubelin Gemological Laboratories (see expedition report and a brief gemological study of Davdar emeralds here). The geological samples collected during that expedition were then provided in 2007 to Dan Marshall with the support of the Gubelin Gem Lab.

For more information about Davdar emeralds, read also the article published in InColor Magazine (spring 2009) about Davdar emeralds in Collaboration with Jean Claude Michelou. (Download the pdf here).

All the best,

May 10th, 2009 | Keywords:ICA , China , emerald , Davdar , Congress Travel |
Blog Title: 13th ICA (International Colored stone Association) congress: Pan Yu, China

13th ICA (International Colored stone Association) Congress Panyu, China: May 06 - May. 09, 2009...
I'm just back from China and the 13th ICA congress. It was not really something I could qualify as "field gemology" but nevertheless before to go to the field, one very important thing is to get the right contacts. And for this the ICA is a wonderful association to become a member of as many ICA members are gemstone miners or well connected dealers. If you come to them with the right project they might be able to help you as they were able to help me since 2004 when I became an ICA member. Believe me: That was a good move as without the ICA and its members I would not have been able to visit many of the countries I visited in the past five years.
The congress was cosy and comfortable. I Found it very interesting on many aspects: It was first a new occasion to remind that the gem trade is not really about gemology, science, art or even regulations even if all these aspects have also their importance. In fact the gem trade is mainly just about people...
And there I was to meet people: Meet old friends and make new friends, it is all what ICA congress are about. But this is great as when you want to go to the field, the most important thing you need is to have a good local contact.
This time China was the highlight, the congress was hosted in Pan Yu, a Chinese city located between Guangzhou and Hong Kong and which is nowadays one of the world's most active gemstone cutting and jewelry manufacturing center. It was very busy and well attended and we had two days with many presentations followed by nice diners and great evening time in the hotel lobby near the white tigers...
I was happy to meet there again my Chinese friends first the two "Chinese Alex": It is quite funny that the two chinese miners I know, one mining sapphires in Shandong and another mining emeralds in Xin Jiang, are both named "Alex" and finaly my former student at AIGS: Paul S.Y. Chan who has a company in Pan Yu. Paul was great to introduce me and other friends to several interesting people and companies in Pan Yu at the beginning of the congress and later while he was taking Richard W. Hughes, Ron Ringsrud, Mariana Photiouand my GIA teammate Robert Weldon to visit to the "Worldmart Gemstone Boulevard"and the "Jade Market" just before my return to Bangkok: Thanks Paul!

"China and gemology: A complicated passion"
The author taking a photo of jade bangles in the Guangzhoujade market with Paul S.Y. Chan on the right.
The photo is mix of green gems, people, mirror effects and the complicated network of jade circles contrasting with the author "sapphire crystal shape glasses design" is interesting to illustrate the author feeling about this congress.
Photo: V. Pardieu / GIA Laboratory Bangkok, 2009

The congress was very interesting regarding many aspects: We saw first how Chinese officials were in love with statistics, official speeches and regulations. We saw also that the NGTC (National Gemstone Testing Center) seems to be a considerable force inside the country and that in China the word "order" means something... That was probably something that the Chinese wanted us to see and that was indeed very noticeable... Nevertheless it was not my first visit in China and I was then not very surprised.
After 2 days of a nice congress it seems to me that the main challenge between Chinese people and the rest of the world seems nevertheless to be still and probably again for a while the language barrier. If the presentations were translated using simultaneous translation techniques, the process which was technically a success was not without surprises for me:
Two of these surprises are possibly a good example of the difficulties people and organizations might encounter while doing business in China:
We had a lab panel where gemstone "reports" were commonly translated into gemstone "certificates" and where instead to have a dialogue we had mainly a monologue with a powerful chinese lady using the panel as a personal tribune. That was interesting.
The second language surprise I had was that in the official translations the word "Emerald" was translated into "Fei Cui" meaning "jade". Nevertheless most people I know told me that they know that emerald and Jade are different and that in Chinese there are words for "emerald", something like "Dju Mu Lu" or "Lo Bow Chu" but may be these words were seen as local slang by officials or possibly also the translators had only a limited gemological knowledge... The mistake might not seems important as people told me that most people understood that we were speaking about emeralds and not about jade but what about the people with no or just limited gemological knowledge?
These issues are in my opinion quite typical about the challenges doing business in a foreign country where language issues are common. Don't get me wrong, it is not just about China, I saw that in many other places while traveling the world. But it seems to be particularly true with China despite the numerous efforts the Chinese are obviously doing. Anyway, that was to be expected as modernizing such a huge country is something that will take some time and that will need some understanding and help from the rest of the word. But slowly and slowly, things will probably continue to improve for the benefit of all.

My main task for the congress was to give two presentations:

The first one was a presentation of the GIA "colored stone grading system", a system I studied at GIA Thailand in 2001l. As a former GIA student, it was a pleasure and an honnor to present to the congress public this system which provides a systematic and repeatable method to undertand and communicate about color and evaluate colored gemstones.

My second presentation was about emeralds from Davdar in the western Xin Jiang province of China, a new emerald deposit I visited in 2006. I was working on this subject since my visit at the mines with Alex, the english speaking son of the Davdar Chinese miner, Dietmar Schwarz, the Director of Research at the Gubelin Gem Lab in Switzerland I was working for in 2007 and 2008 and with geologist Dan Marshall from the Brendan Fraser University in Vancouver, Canada. This was the only presentation in the congress about a Chinese gemstone deposit. It was then an honor to get such opportunity to introduce to the people present at the congress these promissing new deposit. My 30mn presentation seems to have been very well appreciated by the people who attended the congress despite a small technical problem: I sent my presentation few days before the congress. At the congress I came with an update that I placed in the congress computer in the morning as I got new photos and was able to make it better in the few days before the congress. It seems to me that when the technical people copied the other presentations in the computer for the afternoon presentations they replaced my new version with the older version: My mistake was obviously to have kept the same name for the update in my computer... I did not notice the problem before to start my presentation but slide after slide; I realized that there was something really wrong. So I had to change all what I had in mind and present the old version instead of the new one... Too bad, but well: These are things that happen and next time i will for sure be more careful when i will update a presentation!
Despite the stress, I was able to keep my tone as regular as possible and to present what was showing on the screen. It could have been much better for sure but it seems that it was not bad as many "emerald people" came later to speak to me and to the emerald miners. Obviously they had appreicated it and I was able to get them interested by these new gems, whihc was my main purpose.
The miners were also happy: This is a good example about what this website is about: Miners usually agree to help a visiting gemologist to visit their mine if they can expect to have in exchange some kind of promotion for their gems. On my expedition reports are accessible not only for people in consuming country, who can also get easily an access to many gemological publications, but these reports are also accessible for people in producing countries hwo face difficulties to get gemological books and litterature. People in producing countries can then read the result of our work.
Thanks to this type of collaboration: The miner get some exposure and some promotion for his production, the gemologist the samples he need to study and the gemological community the first hand information they need.

As Jack Ogden, the Gem-A CEO told me during the congress with humor: "Research without publications is masturbation." Jack is right: Publications are very useful to build productive collaborations.

It was great to meet again Alex, his mother and his girlfriend at the occasion of this congress and it was a pleasure to give to their promissing emerald deposit some promotion at that occasion. It was a great honnor to introduce this new deposit to the people attending the ICA congress and a pleasure to see that it created a lot of interest. I was also very happy to get from Alex Chang some additional samples for the GIA reference gemstone collection, that will be useful to complete our researchs based so far only on the few samples I collected at the mines in 2006. Thanks to them we will be probably able soon to produce an interesting "On-going research" publication on GIA Laboratory Bangkok website and possibly a nice article for Gems and Gemology.

"Silk road emerald from the miner to the loved one"
Left: Davdar emerald miner Alex Chang presenting a piece of sandstone introduced with a vein with a beautiful emerald mineralization and on the right Alex girl friend is presenting a lovely Davdar emerald set on a ring a lotus Chinese design.
It is not that common to see the miner and the final consumer together...
I wish this lovely couple all the best!
Photo: V. Pardieu / GIA Laboratory Bangkok, 2009

This congress was not just about giving a presentation and writting an article about Davdar emeralds with JC Michelou: Alex came with some new samples from his recent production in order for me and the GIA Laboratory Bangkok gemologists to continue working on these interesting gems.
These samples will be useful in order to continue our studies on Davdar emeralds and to increase a little bit more our knowledge about these fascinating gems. He also provided me some new photographs of the recent mining activity there. If I was not able to show these photos during my presentation to the people attending the ICA congress I will nevertheless add them soon on the Emeralds from Davdar page and they will be also useful to illustrate our coming article on the subject on GIA Lab Research pages.

"ICA Networking"
As an illustration about what ICA congress are about: People meeting other people sharing the same passion: Here are several "emerald people" around Davdar Chinese miner Anyur (Alex's mother) holding a Davdar mineral specimen:
Left to right: Gabriel Angarita, the young president of the ACODES (the Colombian association of gemstone exporters), ICA Vice President and emerald connoisseur Jean Claude Michelou, gemologist Dietmar Schwarz from the Gubelin Gem Lab., one of the world's leading gemologists regarding emeralds I had the pleasure to work with at the Gubelin Gem Lab on the Davdar emeralds and finally American emerald dealer Ron Ringsrud who just published a beautiful book about emeralds.
Photo: V. Pardieu / GIA Laboratory Bangkok, 2009


Participating at the ICA Congress I had the pleasure to meet finally Ron Ringsrud who was present with his new book on emeralds: "Emeralds, A Passionate Guide".
That book was my best gemological litterature surprise for long: It is a book about about the passion for emeralds and about emerald people. It contains a lot of very useful information for all people interested by this gem. Truly it is a book that all people from the hardcore gemologist to the lady curious about the gem she was given as a present, should consider to read as they will probably enjoy it and learn a lot from it.
On my side: I love it and I'm happy to recommend it.
Bravo Ron! All the best!

Finally it was again a great congress where we were all able to network with many new people and meet again with good friends. We were able to speak about different new projects which I hope will be succesful and useful for the gemological community and the gem trade. The fact is that the ICA congress are wonderful events to meet people, network and initiate projects. I would like then to thanks the ICA and the people from China to have organized such a nice event in Pan Yu. It was a pleasure to have participated and I hope that this would have been useful for both ICA and GIA..
All the best,

September 27th, 2006 | Keywords:China , emerald , Davdar Travel |
Blog Title: China 2006

A visit to the new Chinese emerald mines in Xin Jiang (Summer 2006):

The whole expedition report is avaliable at that link:
Itpresents the field expedition Vincent Pardieu, then Director of the AIGS gemological laboratory in bangkok, Thailand had with his former student Guillaume Soubiraa to new emerald mines in Xin Jiang western province of China. This fieldtrip was part of the larger expedition supported by the AIGS Gemological Laboratory (Thailand), the Gubelin Gem Lab (Switzerland) with the help of ICA to the Central Asia. The purpose was to visit ruby, spinel and emerald deposits.

The Davdar emerald mining was first reported in the gemological litterature by Dudley Blauwet in Gems and Gemology (Spring 2005, GNI p 56-57) If Dudley Blawet was not able to visit the deposit he provided nevertheless some very useful information about the deposit and also some stones (bought in Pakistan) to the GIA Laboratory that were studied by Elizabteh P.Quinn.

We got more details about that new deposit in Namak Mandi gem market in Peshawar (Pakistan) and also while visiting the emerald market in Mingora (Swat Valley, Pakistan). We got then the support of Mr. Parveez, an Afghan Pakistani gem dealer who had some interest in the emerald deposit in Xin Jiang and agreed to help us to visit it.

We travelled to Kashgar (Xin Jiang province of China) by plane from Islamabad (Pakistan) where we met our local contact thanks to Parveez support. We visited a bit the gem market in Kashgar and took the Karakoram highway south to Tashkurgan in order to do the necessary paperwork to be able to visit the new emerald deposit located at Davdar, between Tashkurgan and the Pakistani border. As all Chinese border area, beyond the last immigration check point, it was then necessary to get a special permit to go there. Thanks to our Chinese friends we got that permit within 2 days and were able to proceed on our visit to the mining site.

According to the local people, emeralds were first found near Davdar village in 2000. The existance of the new deposit remained secret for few years (until 2005) the production, mostly illegal, was reported to us to have been traded through Peshawar and Dubai. We were probably the first gemologists to reach these new mines on August 01, 2006. During our visit we visited 2 mining concessions: The first place was worked in the past by a Pakistani/Chinese joint venture and the second was operated by a private Chinese company. After one full day visiting the mining area and collecting samples on site, we left China taking the Karakoram highway south to Pakistan through the famous Kunjerab pass (4733 meters altitude) which is the world higherst border crossing. After a short stop in Sost we reached Gilgit late at night and then returned to Islamabad to continue our Pakistani expedition.

"Guillaume Soubiraa who travelled with the author for about 3 months in Central Asia in 2006 from Pakistan to Afghanistan, Tajikistan and China with at the background the emerald mining site at Davdar, Xin Jiang Province, China."
Photo: V. Pardieu/AIGS/Gubelin Gem Lab/ICA, 2006


At the end of that expedition report you will also find a "short study about Emeralds from Davdar, Xin Jiang, China".

All the best,

Important Note: Vincent Pardieu is an employee of GIA (Gemological Institute of America) Laboratory Bangkok since Dec 2008. Any views expressed on this website - and in particular any views expressed by Vincent Pardieu - are the authors' opinions and do not necessarily reflect the opinions of GIA or GIA Laboratory Bangkok. GIA takes no responsibility and assumes no liability for any content on this website nor is GIA liable for any mistakes or omissions you may encounter. GIA is in particular not screening, editing or monitoring the content on this website and has no possibility to remove, screen or edit any content.