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.
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.
Index page: Vincent Pardieu's Blog
About the Author
About me : How did a countryside Frenchman became a "Shameless travel addicted gemologist"? ( Under construction)
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:
- Introduction to AIGS/ICA/Gubelin Gem lab 2005 Expeditions
Special 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 STUDY GEMOLOGY?
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:
Photos by Vincent Pardieu, Jean Baptiste Senoble (Nomad's, Bangkok, Thailand) Guillaume Soubiraa () Michael Rogers ()
The 2005 and 2007 expeditions were supported by the Gubelin Gem Lab located in Luzern, Switzerland, as the 2005 expedition was financed by the Gubelin Gem Lab and the AIGS Gemological Laboratory in Bangkok, Thailand and, because at the time of the 2007 expedition the author was working at the Gubelin Gem Lab as a gemologist.
Introduction to the Rockland ruby mine also known as the "John Saul Ruby mine":
Kenya most important ruby mines are located in the south of the Tsavo national park, in an area known as the Mengare swamp. The area has two deposits located few hundred meters away from each other: The "John Saul ruby mine" on the west and the "Penny Lane mine" in the east. Currently the company "Rockland Kenya" is mining the John Saul Mine, while three companies: "Aqua", "Equator" and "Hardrock" are mining at "Penny Lane".
According to "Ruby and Sapphire" by Richard W.Hughes, "The deposits were discovered in 1973 when American geologist Jon Saul and Elliott ('Tim') Miller were prospecting in Kenya's Tsavo West National Park for chromium and vanadium bearing gemstones when they found what has become one of the world 's richest deposit of ruby." Additional information about this discovery and the John Saul ruby mine is found on Swalagemtraders: John Saul sons website.
During our visits in 2005 and 2007 of the Mengari swamp mines we could confirm the words we read in ruby lover's bible: "Ruby and Sapphire" by R.W. Hughes: "Rubies of the John Saul mine tend to be lighter and brighter than those from Penny Lane, displaying a rather strong pink to purple-pink element. The vast majority of the stones are of fine cabochon to sub cabochon grade, but occasionaly a fine small clear piece is found. All are intensively fluorescent under UV light and at times ressemble Burmese rubies. However the Kenyan stones are generally filled with thick, wispy fluid fingerprintss and feathers, unlike unheated stones from Burma."
The ruby deposits of this area are the result of complex metasomatic interactions between metasomatic fluids, quartzo-feldspathic precursors such as felsic gneisses and pegmatites, and carbonatised ultramafic bodies. The geology of these deposits was studied by different authors (Austomineral GmbH, 1978; Key and Ochieng, 1991; Mercier and al, 1999; Simonet, 2000.) According to Simonet, a French geologist who was working at the John Saul mine as geologist for Rockland Kenya:
"The ruby deposits of the John Saul mine are all directly associted with a rounded ultramafic body that consist mainly of enstatite, talc and carbonates. This ultramafic body is probably the remant of a disrupted ophiolite (simonet, 2000a) and the current mineral assemblage is the result of metamorphism of a peridotite under a high CO2 pressure (Mercier and al, 1999). The body is 150m long and 100 wide, and about half dozen corundum veins are present around it. Although all are the result of metasomatic interactions between felsic rocks, ultramafites and metamorphic fluids, each shows different characteristics: size, shape, mineral assemplages. This variety is due to differences in the nature of the protoliths, in the P-T conditions, and the chemistry and history of the mineralising fluids."
We invite you to follow our 2005 and 2007 gemological expeditions to Kenya using the potential given by the free software Google Earth. Just download and install the software, then using our links you can get a better idea about the mining areas we visited or those for which information is available in the gemological litterature. We recommend you to select the "terrain" option (down left in the "layer" booklet) in order to enjoy a 3D visit.
Using our Google Earth placemarks, you can now follow our expeditions and explore East Africa downloading the placemarks we prepared. Just download them clicking on the icon on the left to fly to Kenya and Tanzania
Tsavo: A name evocating one of Africa largest National Park is also the homeland of some of the most interesting ruby mines in the world. In July 2005 when we first visited the Rockland Kenya Co Ltd operating the John Saul Mine, we met near the entrance of the mine a herd of more than 100 elephants.
(An elephant in the bush few hundred meters from the John Saul Mine, Photo: V. Pardieu 2005)
In October 2007 when I returned to the mine, Rockland was completing a barrier and a depp trench to protect the operation from these massive animals searching for water during the dry period.
July 2005: Alfonse Mwanda, General manager of the John Saul mine operation for Rockland Kenya Co Ltd is taking us for a visit of the mine. The first mining pit we visited was the "Mila" open pit in which a team of miners was working with a young German geologist from Paul Wild company in Idar Oberstein, Germany as Paul Wild and Rockland Kenya are partners in this operation. The Rockland Kenya operation in October 2007 is an 82 people operation including 24 miners and a geologist. The rest of the people working at the mine are machine operators, gem sorters, cooks or security guards. The Rockland mining operation is very different from most of the other gem mining operations we visited in east Africa, except may be the Tanzanite One operation in Merelani Tanzania, as it is a large modern mining operation with a high level of organization and security.
October 2007, Micheal Rogers, Rockland Kenya's geologist Meshack Otieno and the author are examinating some ruby bearing rocks near the entrance of the new Kitonga pit which was started in 2006 after one year of prospection.
October 2007: Gemologist Michael Rogers holding a piece of ruby rich rocks, near the entrance of the Kitonga mining pit:
July 2005: Rockland Kenya "John Saul's mine" General Manager Alfonse Mwanda present us different ruby rich rocks near the entrance of the Kimbo mining pit.
October 2007: A view over the new Kitonga pit. From these rounded shafts 3 horizontal galleries were dig at 10, 14 and 22 meters deep. The presence of the 2 vertical shaft enable a better ventilation inside the mine.
Rockland Kenya geologist Meshack Otieno explaining to us the work at the Kimbo mining pit.
July 2005: A view down to the Kimbo pit which was more than 30 meters deep.
October 2007: A view down the second Kitonga mining pit, this shaft is used for ventilation. The miners are using the other rounded pit in order to go to work in the mine galleries using a lift as we also did during this visit.
October 2007: 14 meters underground, miners working at the Kitonga pit.
October 2007: Inside the Kitonga pit, the tunnels are high enough for men to walk and reach after about 40 meters the current working area.
In the tunnels of the John Saul mine, we were impressed by the level of organization of this mine which is not common for a ruby mine.
Video: V. Pardieu, Oct. 2007.
In the deep of the Kitonga mining pit the miners are working using machinery.
Rockland Kenya General Manager Alphonse Mwanda inspects with Guillaume Soubiraa some ruby rich rocks just taken from the ground in the deep of the mining tunnels at the Rockland Kenya ruby mine.
Video: V. Pardieu, Oct. 2007.
A miner working in the deep of the john Saul Mine at the Kitonga Pit.
A hand full of rubies from the Kitonga mining pit:
A view from the Kimbo mining pit we used during our visit in October 2007 to return to the surface. On the second photo young gemologist Guillaume Soubiraa is getting a remember from his visit at the John Saul mine...
October 2007, On the way back from the Kitonga and the Kimbo mines.
July 2005: Rockland Kenya General Manager Alfonse Mwanda welcome us to the mine plant, technically known as a “sink-float” plant were rubies are processed.
Nice "John Saul's Mine" ruby samples in some marble matrix with as background the mine plant. At the John Saul Mine rubies can be found in different rocks as Cedric Simonet explains: "The "John Saul Mine" body is 150m long and 100 wide, and about half dozen corundum veins are present around it. Although all are the result of metasomatic interactions between felsic rocks, ultramafites and metamorphic fluids, each shows different characteristics: size, shape, mineral assemplages. This variety is due to differences in the nature of the protoliths, in the P-T conditions, and the chemistry and history of the mineralising fluids."
On the following photo it is easy to get a clear idea about the huge ruby production of the "John Saul's Mine". But of course all these stones are not gem quality, only less than 1% of these stones will be transparent enough to be faceted and probably only after a succesful heat treatment. Most of these stones will be to the best cabochon grade or possibly attractive mineral samples.
On the following photo rubies get sorted and separated from their matrix at the Rockland mine.
On rubies and other gems from primary deposits needs to get separated from their host rock, in many mining areas including the Rockland mine, this is performed manually.
A mine worker separating some low quality rubies from its matrix.
The rubies are then cleaned before to be sorted.
A basket of John Saul mine rubies at Rockland Kenya during July 2005.
In 2006, the John Saul mine production was told us to have been about 6 tons of ruby material, but only 40% was told us to have been suitable for heat treatment and less than 0,5% meaning about 30 kg was told us to have been of "gem quality".
On the following photo taken at the headquarters of Rockland Kenya in Nairobi, you can discover some ruby crystals from the John Saul mine together with some heat treated ruby cabochons and few small unheated faceted rubies showing the classic color of most ruby production from the John Saul Mine.
Notes about the Kenya gemstone mines pages (Edited on Oct 10, 2008)
These "Gemstone mines of Kenya" web pages presents the result of the two gemological expeditions to East Africa in Jul. and Aug. 2005 and Oct. 2007. They were build with the support of ICA (The International Colored Stone Association) and particularly of ICA ambassador to Kenya Suzie Kennedy and her husband Kennedy Khamwati for the Kenya part. Kennedy was nice enough in 2005 to take us to visit all the ruby and tsavorite mines we wanted to visit. His help, presence and permanent support was highly appreciated. In Oct 2007 we were helped in the field by ruby and tsavorite miner and ICA member Genson Micheni Musa, the owner of the Tsavolite mine near Tsavo. Micheni support was also very much appreciated. I want here to dedicate these pages to Kennedy and Micheni as without them I would not have been able to collect and share all these notes about gem mining in Kenya.
The Jul. and Aug. 2005 expedition was a join expedition by the AIGS gemological Laboratory in Bangkok, Thailand (where I was then the Laboratory Director) and the Gubelin Gem Lab, in Lucerne Switzerland. I was then traveling with Jean Baptiste Senoble, one of my former AIGS gemology student, working as I write these words in 2008 for Nomad's Co Ltd, a Bangkok based gem dealer.
The Oct 2007 expedition was also part of a larger expedition to East Africa I lead in collaboration with gemologist Richard W. Hughes. I was then gemologist for the Gubelin Gem Lab. Two young gemologist and former AIGS students: Guillaume Soubiraa and Michael Rogers joined me in this expedition as well as One of Guillaume Soubiraa friends from Madagascar: Philippe Brunot.
The purpose of these expeditions was to visit ruby, sapphire, alexandrite, emerald, tsavorite, tanzanite and tourmaline mines in Kenya and Tanzania for gemological research purpose. Origin determination of gemstones like rubies and sapphires is an important part of the daily work at the Gubelin Gem Lab and it is important for a gemologist specialized in origin determination of gemstones to collect data directly at the source in order keep his knowledge of the world gemstone mining areas updated. As a former tour guide, turned into a gemologist, it is my pleasure to share the benefit of these expeditions with you and I hope that it will benefit to the people who welcomed and helped us in the field.
Please visit the other Kenya pages on fieldgemology.org:
Special thanks, to all the Kenyan authorities we met which provided us support and help, to the miners who welcomed us at their mines, shared with us their time and their life. Your support and welcome was much appreciated! I hope that this report will be useful to all people we met in Kenya and to all the people interested in the gem trade from the production areas in Kenya to the consuming markets and for all gem lovers around the world.
Now I would like to give a more personal thanks to the following people as without their help and support during these expeditions to Kenyia, I would not have succeded in these expeditions:
First thanks to my traveling companions which helped to finance, to organize and to make this expedition a succes:
Jean Baptiste Senoble currently working for the Nomad's company in Bangkok was my gemology student at the AIGS, in Bangkok and became then one of my regular traveling companions to gem markets and mines around Bangkok. He was my traveling assistant during the 2005 gemological expeditions to Vietnam, Sri Lanka, Madagascar, Kenya and Tanzania. We returned together in Tanzania and Madagascar in 2008. Without his help and support these expeditions would not have even been possible. All the best to you JB!
Guillaume Soubiraa (from SMDA in Madagascar) and Mike Rogers, two former students of the AIGS in Bangkok and Philippe Brunot, one of Guillaume childhood friends from Madagascar were my travelling companions while visiting Kenyan ruby and tsavorite mining areas in October 2008. Thanks to their presence, support and presence this expedition turned to be a pleasure and a success.
All the best guys and great thanks!
These 2005 and 2007 expeditions to Kenya tsavorite and ruby mines would not have been possible without the help of local members of the Kenyan gem trade:
Suzie Kennedy is the current ICA Embassador to Kenya. With her husband Kennedy Khamwathi, they are some very active members of the Kenyan gem trade. Our 2005 and 2007 expeditions were possible thanks to their help and support.
The presence of Kennedy each day during all our 2005 expedition was very much appreciated and so useful to the succes of this expeditions. Really thanks to both of you!
Genson Micheni Musa is a Kenyan ruby dealer which turned into a tsavorite miner in Kasigau area. His mining company "Tsavolite" is located just near the famous Tsavo National Park. Micheni was a wonderful and friendly guide during our October 2007 expedition. His knowledge of the Kenyan gem trade and of the Tsavo area was very useful to the success of our expedition. Thanks Micheni!
Finaly I dont want to forget to thanks the Gubelin Gem Lab in Luzern, Switzerland, my fellow gemologists and colleagues working there for their support in the realization of this expedition.
Interesting Links and recommended readings about gemstones mining in Kenya:
Interesting Links and recommended readings about ruby and sapphire from Kenya:
"Geology of sapphire and ruby deposits - The example of the John Saul Ruby Mine, Mangare, Kenya": The PHD thesis of Dr Cedric Simonet. A must to read work for those interesting in Kenyan ruby and sapphire deposits. "General setting of coloured gemstone deposits in the Mozambique Belt of Kenya" and other publications about gem deposits in Kenya on Cedric Simonet's kasigau.fr website. "Geologie and gem deposits of Kenya" "The Kimbo ruby deposit": An excellent study of the John Saul mine by Dr Cedric Simonet, a former manager of the mine for Hard Rock Mining. "The John Saul Ruby mine": On Swala Gem Traders website, an interesting article about the discovery of rubies in Tsavo by American geologist John Saul. "Savanna rubies ": by Creative Gems, an interesting attempt to brand rubies from Tsavo. "With Open arms" A Kenyan farmer found precious bounty in his barren fields. By Denis Maina Gathanju "Star sapphire from Kenya", N.R. Barot, A.Flamini, G.Graziani, E.J. Gubelin, Journal of gemmology, 1989,21,8 "A new sapphire deposit, turkana, Kenya", T. Themelis, Gemological Digest, Vol.2,No.4,1989 "The Growth of rubies in south -east Kenya" R.M. Key and J.O. Ochieng, Journal of Gemmology,1991,22,8 "Pink sapphire from Kitui, Kenya", Dr N.R. Barot and Dr R.R. Harding, Journal of gemmology,1994,24,3 "Chemical fingerprinting of some East African gem rubies by Laser Ablasion ICPMS" A.H. Rankin, J. Greenwood, D. Hargreaves, Journal of gemmology, 2003,28,8,pp.473-482 "Kenyan rubies exported to Thailand", Gems and gemology, Winter 1986, p.247 "Update on ruby output in Kenya", Jewelry News Asia, No170, October 1998, p.63 "An update on the John Saul ruby mine", Gems and gemology, Winter 1999, pp.213-214 "Exotic origin of the ruby deposit of the Mangari arera in SE Kenya" A.Mercier, P.Debat, J.M. Saul, Ore Geology reviews, Vol.14,1999,pp.83-104 "The Dusi (Garba Tula) sapphire deposit, central Kenya - A unique Pan African corundum-bearing monzonite" C.Simonet, J.L. Paquette, C.Pin, B. Lasnier, E. Fritsch, Journal of African Earth Sciences, Vol.38,No.4,2004,pp.401-410 "Saphirs et rubis, Classification des gisements de Corindon", Le Regne Mineral, No.55, Jan-Fev. 2004 "Rubin, Saphir, Korund, Schon, Hartselten, kostlar", extraLapis No15, 1998
Interesting Links and Bibliography about Tourmaline in Kenya:
"Golden tourmaline from Kenya" Gems and Gemology, Summer1996, pp.135-136 "Colour-changing chromiferous tourmalines from East Africa" Prof. Dr H. Bank, Dr U.Henn, Journal of gemmology, 1988,21,2,pp.102-103 "Geology of theYellow mine (Taita-Taveta district, Kenya) and other yellow tourmaline deposits in East Africa" Dr.C.Simonet, Journal of gemmology, 2000,27,1,pp.11-29 "Les tourmalines magnesiennes d'Afrique de l'Est", C.Simonet, Revue de gemmologie AFG, Septembre 2006, pp.4-7
Interesting Links and Bibliography about Tsavorite:
"Gemstones from East Africa" by Peter C. Keller (1992)
"Ruby and Sapphire" by Richard W. Hughes (1997)
Interesting links and bibliography about Tsavo
"The Man-Eaters of Tsavo" by Colonel J.M. Patterson. Hardcover: 346 pages. Publisher: Saint Martin's Press (Jan 1986), ISBN: 0312510101 "The Lions of Tsavo: Exploring the Legacy of Africa's Notorious Man-Eaters" by Bruce D. Patterson. Hardcover: 324 pages. Publisher: McGraw-Hill Education (Sep 2003), ISBN: 0071363335 Romanticized Hollywood movie: The Ghost And The Darkness  ; DVD ~ Michael Douglas; Studio: Paramount Home Entertainment (UK); DVD Release Date: 3 Dec 2001; Run Time: 105 minutes
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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.