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:

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Find our photos using the following Keywords:

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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,

October 7th, 2009 | Keywords:Tanzania , Meralani , tanzanite , tsavorite , Travel |
Blog Title: Minerological Record article about Merelani

New Publication: Merelani, Tanzania published by "the Mineralogical Record", Sept-Oct 2009 Vol. 40 Number 5:

I would like to invite you to read the new publication I collaborate with about the Merelani mining area in Northern Tanzania: This article was recently published by "The Mineralogical Record" It was written in collaboration with Wendell E. Wilson, John M. Saul and Richard W. Hughes.

The origin of the article was the report of the 2007 expedition I had with Richard W. Hughes, Guillaume Soubiraa, Mike Rogers, Monty and Warne Chitty and Philippe Brunot.

Thanks to the contributions of Richard W. Hughes, John M. Saul and Wendell E. Wilson this expedition report turned into a terrific 63 page article beautifully illustrated with many photos of some of the finest Tanzanite, tsavorite, Axinite and diaspore crystals ever mined in Merelani.



"Merelani, Tanzania "
The Mineralogical Record, September-October 2009

It was a pleasure to collaborate to this article and even more to read it. I hope that you will enjoy it as much a I did.

All the best,




September 5th, 2009 | Keywords:Tanzania , tsavorite , tanzanite Travel |
Blog Title: FE09, Part 01: Arriving in North Tanzania

GIA FE09 (GIA Laboratory Bangkok Field Expedition 09): Part 01: Aug. 29 - Sep. 02, 2009: Tanzania:

This is the first part of the GIA Field Expedition to East Africa, I'm leading for the GIA Laboratory Bangkok: I arrived in Arusha, Tanzania from Bangkok with Canadian gemologist Lou Pierre Bryl on Aug. 28th 2009 in the morning. We were joined there in the evening by Swiss gemologist Stephane Jacquat.

Our first task was to prepare the things for the coming expedition to Mozambique and Tanzania scheduled for Sept 2009. We met our usual local Tanzanian contacts: Mark Saul from "Swala Gem Traders", Abdul Y. Msellem, a Tanzanian broker I had already as guide in 2005, 2007 and 2008 and Moussa our driver (from Fortes Safaris). Thanks to their support after a short visit to the Arusha mining officer and few phone calls to different miners, we got rapidly everything ready regarding our vehicle, our schedule, the necessary paperwork to enter the mining areas.

Few hours after our arrival we could start our visit with the Arusha market and the "Tanzanite Experience", a very interesting museum dedicated to Tanzanite located just opposite of the Tanzanite One office in Arusha. There we could have a very interesting visit. That museum really worth the visit as at the end we had the pleasure to be able to see and manipulate a very fine and large Tanzanite crystal which is used for demonstration:

"Tanzanian beauties"
Teddy Kallaghe, a sales staff at the "Tanzanite Experience" in Arusha is presenting us a fine tanzanite crystal reportedly unheated.
Photo: V. Pardieu/GIA Laboratory Bangkok, 2009

The next day on Aug 29th, with the help of Tsavorite miner Rafael Manyosa, we traveled to the new tsavorite deposit at Namalulu, a small village located south of the Lemeshuko and Lendanai areas. The areas was reported to have been discovered in Aug 2008 by Massai "moranis" (young Massai "cow boys"). Rapidly two Massais: Mr. Urubundu and Mr. Saruni started to mine the area. Within few months in Dec. 2008 about 500 people were mining and trading tsavorite at Namalulu. Then as it was necessary to go underground to do hard rock type mining, we were reported that many miners left to go to mine at the Lemeshuko area after the departure of the Saul Brothers when they closed their mine at the end of 2008. At the time of our visit about 150 people were mining in Namalulu. There was 3 important and deep underground mining operations and several smaller ones. After meeting the local miners and explaining the purpose of our visit we were able to visit 3 mining pits: First the Yoshua Kivuyo (Massai miner) pit which was about 30 meters deep, then the exploitation from Rafael Manyosa (our guide) and his Massai partner: Mr. Kikanai. There we were lucky to witness the discovery of a fine tsavorite pocket. Finally we visited the mine of Mr. Saruni, a very deep mine (about 150 meters) which is also one of the oldest as Mr. Saruni was the second miner to start working at Namalulu.

"Rough green gems from the Massai steppe"
A Massai miner is presenting us a parcel of rough tsavorite he found mining underground in Namalulu.
Photo: V. Pardieu/GIA Laboratory Bangkok, 2009


For the following 2 days we decided to focus on Merelani, where Tanzanite is mined:

On Aug. 30 we travelled to Merelani to visit the "Bedui Camp" mine located in the Karo area (Merelani bloc D"). The Karo area is famous to have produced not only Tanzanite but also some very large tsavorite. Using wooden ladders and ropes we went down to the deep of the mine where we could study the local geology. The visit was easy as it was Sunday and the miners were on week end: As nobody was working there at the time of our visit the mine was not too dusty and it was more easy then to breath and study the rocks 300 meters underground.

"Hope is the Merelani miner mistress... Hard work his daily life."
"Rasta man" is mining underground in Merelani for nearly 20 years,
He was our guide, 300 meters underground visiting the "Bedui Camp" mine in Karo area, Bloc D", Merelani.
Photo: V. Pardieu/GIA Laboratory Bangkok, 2009

On Aug 31, we visited the "Tanzanite One" operation located in Bloc C at Merelani. The visit was again very interesting starting with some good explanations about the local geology with geologist Vitus Ndakize then a visit of the "Investor pit" with Mining Engineer and Manager Damien Massala and finally Mervyn Dettmer took us to visit the processing plant and the sorthouse.

A truly very interesting visit, particularly after visiting a mine in Karo area.


On Sept 01 we took the bus to Dar Es Salaam in order to fly the next day to Nampula in Mozambique to start the second part of this GIA FE09 expedition to East Africa with a visit of the famous tourmaline deposit in Mavuco (near Alto Ligonha) and the two new ruby deposits in Niassa and Cabo Delgado provinces.

All the best,

July 30th, 2008 | Keywords:Tanzanite , Tanzania Travel |
Blog Title: Working the blue Seam

Working the Blue Seam, the Tanzanite mines of Merelani:


This article was published in the Australian Gemmologist July September 2009, Vol. 23, Number 11. pp. 482–494.
For that article author Richard W. Hughes used as inspiration the expedition report by author Vincent Pardieu published on this website after the Oct. 2008 joint expedition they had in Tanzania.

The article is currently available online on and also on Richard W. Hughes website:



"Working the blue seam, the Tanzanite mines of Merelani"
Photo and artwork: Richard W. Hughes.


As usual it was a pleasure to work with Richard on such article. Thanks Richard to have taken the time to do the necessary to improve that report...

November 25th, 2007 | Keywords:Tanzania , Hughes , Merelani , Morogoro , Mahenge , Songea , Tunduru , Ruangwa , Lendanai , Komolo , Manyara , Lemshuku , ruby , spinel , tsavorite , tanzanite , emerald , alexandrite , tourmaline , moonstone , garnet Travel |
Blog Title: Tanzania 2007

Expedition to gemstones mining areas in Tanzania: (October 2007):

Introduction: This report (in two parts) presents the details of the field expedition to Tanzania lead by the author in October 2007. The author was then working as a gemologist for the Gubelin Gem Lab in Lucerne, Switzerland when his friend Richard W. Hughes (working then at the AGTA GTC Laboratory) asked him if he could help him to visit Tanzanian gem deposits in East Africa. After some difficult negociatiosn with his laboratory the author was allowed to take some holidays and travel to Tanzania with Richard W. Hughes and his group.

The group was composed of Richard W Hughes, the author of "Ruby and Sapphire", Warne and Monty Chitty, Mike Rogers, Guillaume Soubiraa and Philippe Brunot. For the expedition we got the support of Mark Saul (From Swala gem traders) and Abdul Y. Msellem a young Tanzanian broker who was already the author guide in Tanzania during his previous visit in 2005.

We started our visit in the north of the country in Arusha.

We travelled first to Morogoro where we visited some moonstone (I should probably say "peristerite"...) and corundum deposits. Then we continued to Mahenge to visit ruby and spinel mining areas. The visit was interesting as it was just few months after the discovery of several huge spinel crystals. Then we took the road to Songea and Tunduru famous for their sapphire mines. After that we continued to Ruangwa to visit its tsavorite mines. We returned then to the north of the country where we visited the Tanzanite mines at Merelani, emerald and alexandrite mines at Manyara, tsavorite mines near Komolo village and tourmaline mines near Lendanai in the Massai steppe.

Two reports are available on (with the old design of, before Dec 2009)

"Tanzania, October 2007, A Gemological Safari. Part 1: Ruby, Sapphire, Moonstone, Spinels, Tsavorite, Alexandrite: Gems from central and south Tanzania"

"Tanzania, October 2007, A Gemological Safari. Part 2: Tsavorite, Tanzanite, Chrome Tourmaline, Emerald and Alexandrites: Gems from the Massai Land (North Tanzania)"



"Mahenge Spinel"
Eric Saul, (from Swala Gem Traders) presents proudly to the author an exceptional red spinel from Mahenge. The stone weighting more than 10 carats is exceptionally clean and is believed to have been cut from one of the giant crystals found in Mahenge during summer 2007.
Photo: V. Pardieu, 2007

This expedition to Tanzania was in fact very succesful not only for the areas visited and the samples collected but also for the contact created with local miners and traders. Few weeks after the author return in Switzerland, his local contact Abdul Y. Msellem informed him of the discovery of a ruby deposit near Winza.

These expedition reports were also the base of two publications in collaboration with Richard W. Hughes:
- "Working the Blueseam: The Tanzanite Mines of Merelani" about Tanzanite mining at Merelani, available both of and
- "Downtown: Gem hunting in Central & Southern Tanzania" about our expedition to the south of the country, available also both on and

Finally thanks to that expedition Warne Chitty was able to get the samples he needed for his Bsc Thesis in gemology and applied mineralogy (Kingston University, UK).

All the best,

September 3rd, 2005 | Keywords:Tanzania , Arusha , Merelani , Longido , Lossogonoi , Umba , Morogoro , Mahenge , Songea , Tunduru , ruby , sapphire , garnet , tsavorite , tanzanite Travel |
Blog Title: Tanzania 2005

A visit to gem markets and gem mining areas in Tanzania (Summer 2005):

Abstract of the Tanzania 2005 page (Available at that link):
This web page presents the field expedition lead by Vincent Pardieu (then Director of the AIGS Gemological Laboratory, Bangkok, Thailand) to Tanzania in July 2005. This fieldtrip was part of the expedition supported by the AIGS gemological laboratory and the Gubelin Gem Lab with the help of ICA to Asia and Africa during summer 2005. During that expedition the author was helped by Jean Baptiste Senoble, a young French gemologist who studied gemology at AIGS in Bangkok in 2005.

That expedition was planned with the support of ICA Member Mark and Eric Saul from Swala Gem Traders in Arusha. With the help of Tanzanian gem broker Abdul Y. Msellem, we visited numerous gem deposits starting from Tanzaniteone (Tanzanite mine at Merelani), Lemeshuko/Komolo (Tsavorite), Lossogonoi and Longido (ruby), we travelled then to the coast and visited the Umba area (sapphire, garnet), we continued south to Morogoro where we visited ruby and spinel deposits in the Uluguru mountains and then near Mahenge. We travelled then south to visit the Songea sapphire mining area and finally the Tunduru area producing rubies, sapphires, and many other gems including spinels, garnets, chrysoberyl, diamonds. We then returned to Arusha after about a month traveling around Tanzania.

"Left to right: Back in Arusha after a month in the field in Tanzania: Jean Baptiste Senoble then 20 years old, Mark Saul and Vincent Pardieu. After 4 months in the field, including some hard time with malaria (for the author) and serious food poisoning for Jean Baptiste Senoble, we were very tired and had lost about 10 kilos each..."
Photo: Eric Saul, 2005



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.