Olivier Segura, LFG – “Our ambition is for our appraisals to be completely transparent”

Marianne Riou

Olivier Segura manages the French Gemological Laboratory (Laboratoire Français de Gemmologie, or LFG), which was founded in 1929 by a customs official, and run by the Paris Chamber of Commerce from 1936 to 2011. Almost 3 years ago, it was taken over by the Union Française de la Bijouterie, Joaillerie, Orfèvrerie, des Pierres & des Perles (UFBJOP), which appointed Olivier Segura, an atypical trader, as its Director. Rubel & Ménasché went to meet him in order to learn a little more about the LFG first of all, but also about the gem certification process, all the more that of diamonds, and about the detection of synthetics.

Olivier Segura, what led you to become head of the French Gemological Laboratory (LFG) in 2011?

I have always had a passion for the mineral, the “stone”. I thus trained in Biology-Geology, and followed with a Masters in Communication. After 10 years in practice in the communications sector, I decided to go back to my first love: I studied Gemology at the GIA in Bangkok (Graduate Gemologist), and then went on to pursue a degree within the University of Gemology in Nantes. I later started a trading company specialized in colored gems. In 2011, when the UFBJOP offered me the post of Director at the LFG, I could only say “yes” to a challenge of this sort.

In what way was it a challenge?

This gemology laboratory was the first in the world. It was suffering from a poor image and many mistakes had been made there: the Paris Chamber of Commerce and Industry did not wish to develop it internationally and there was no marketing support to put its work forward. In short, it was a “sleeping beauty”.

Tell us about the laboratory. Why was it created to begin with?

The laboratory was created in 1929, as a result of the massive influx of cultured pearls on the market. The first ones date back to 1915-1920, and Paris, at the time, already held an important place for this trade as it hosted many buyers. Furthermore, the parallel with diamonds is interesting. Nowadays, 99,9 % of the pearls found on the market are cultured pearls. The natural pearl supply is very limited. They are now only sold to collectors, at auctions, at Sotheby’s or at Christie’s. The word pearl cannot be used on its own (Decree n°2002-65 dated January 14, 2002), notably for cultured pearls, but a semantic shift brought it into general use. There are of course different qualities of cultured pearls but, as far as I’m concerned, they are nothing like genuine natural pearls, which are the product of an unexpected discovery…

What changes did you wish to foster when you took up your post?

Well, I started by polling our clients with the help of a questionnaire. I had to know why the big names of Place Vendôme preferred sending their gems to Antwerp, to Switzerland and to the US for valuation. This is how I noticed we had a problem with the diamond color grading. You must bear in mind that, as far as diamonds are concerned, there is no international standard that enables us to determine colorimetry. The standard colors are specific to each laboratory. As the GIA ran the market, I sent our standard set to them in Carlsbad. We realized we were one grade off with the FGH colors. I did the same with the HRD in Europe – the paragon when it comes to assessing the value of gems (melees and less than 1 carat gems). We noticed the same discrepancy. This enabled us to reassess and reposition our standard set on the color scale. We purchased gems of intermediary colors and DEF colors. Lastly, we carried out a test on a sample from a trader and noted only a 5% discrepancy between our appraisal and that of the GIA.

Actually, what is the acceptable discrepancy between the appraisals of the various laboratories in order to determine the quality and the value of a diamond? How do you explain this discrepancy?

The color is established according to a continuum. The clearest possible gem will be a D. In Europe, each color grade is materialized by the most tinted gem in its category. Some gems can be on the verge of a grade, making their positioning difficult, and we can therefore talk about subjectivity. In order to limit this subjective aspect, three graders analyze the diamonds independently. Their results are processed using a computer and are not passed on to the other graders.

When the gems are sold at auctions, the foreign auctioneers have them re-appraised by the GIA. We did not get any feedback that calls our appraisals into question. We therefore consider ourselves to be absolutely reliable as far as the 4Cs of diamond grading are concerned.

According to you, why does the GIA have such a preponderant role in the beneficiation of diamonds?

The GIA was created in 1932. Geographically, this laboratory always positioned itself in strategic spots: production, cut and trade. They also invented the 4C grading system and are at the cutting edge of research…

Could you quickly introduce your scientific team to us?

The French Gemological Laboratory is comprised of 4 gemologists and myself. We have two gemologists who are each in charge of a department. Aurélien Delaunay, who also graduated from the University of Nantes, is in charge of the Diamonds Department. In all honesty, nothing matches the expertise acquired on the job: reading scientific articles, confronting colleagues, training and research. Aurélien Delaunay and myself are currently preparing a thesis. Our activity is also attached to that of the University of Nantes, notably with Emmanuel Fritsch, our scientific advisor, who was Research Director at the GIA in Carlsbad for more than ten years. We are developing a small research activity and publish as often as possible in the GIA journal, in the Journal of Gemology, etc.

Who are your clients and what are your rates?

30 % of them are Place Vendôme jewelers of international standing. They send us their gems at each stage of the manufacturing process: at the time of purchase, of re-cutting and when they are mounted (except for diamonds, which are no longer appraised once they are mounted, ed.). Their objective is to verify, at each stage, that the gem has not been damaged. Another 30 % of our clients are auction houses, which sell abroad but get their supply in France. Lastly, another 30 % are provincial jewelers and traders.

With regard to diamonds, we are sent very high quality gems, as well as melees, for appraisal. The appraisal of a diamond enabling the validation of the 4Cs costs 35 €. We also provide, upon request, a justified report, which was implemented in 2011. This report describes, over ten pages, the scientific progression of the gem appraisal. Our ambition is for our appraisals to be completely transparent.

I would like to go back to the progression of a diamond that reaches your premises for appraisal.

When a diamond of, let’s say, more than 1 carat, reaches our laboratory, it is first turned into a number. Thus, the gemologists who examine it do not know whom it belongs to. The gem is weighed at ten millionth of a carat and then follows the standard gemological examination process, with the help of advanced tools: it is photographed, subjected to the color analysis by three gemologists, then to that of clarity, also by three specialists. The inclusions are noted and measured in order to enable the assessment of the geological nature of each gem. We first give a clarity grade, and then a cut grade with the help of the Sarin measurement tool (laser mirrors). We end with the spectrometric analysis using the infrared spectrometer, which allows us to determine the type of diamond presented (presence of nitrogen atoms or not, what is their arrangement in the crystal lattice, etc.) If we determine that the diamond is of type IIa, that is to say chemically pure, like the exceptional Golconda diamonds, we verify whether it is natural or synthetic by observing it through the Raman spectrometer.


Actually, what enables you to determine for sure whether a chemically pure diamond, of type IIa, is a synthetic diamond rather than a treated diamond?

To determine whether a diamond is synthetic or not, you need to take a look at its growth. We use the De Beers DiamondView  in order to make the diamonds “luminescent”. Within a certain very specific wavelength, this tool enables us to visualize the growth process (peaks, size): if this growth is cubic, it means that the diamond is synthetic.

The gemological appraisal laboratories decided ˗ by tacit agreement ˗ to present synthetic diamonds in a yellow background report. This has been the done thing for about five years now. For the rest, they are graded according to the same criteria as natural diamonds.

What are your thoughts on the place that these synthetic and chemically pure diamonds could have on the market?

There is obviously a market for this type of gems, just as for synthetic corundums. It is as worthy as any other material. It is a real challenge to create them and they offer incredible opportunities to the industrial sector; just think about space shuttles and high-speed electronics. These diamonds, which have been in jewelers’ shops only for about a year or two, are therefore exceptional. On a ring, they certainly look better than a piece of glass or zirconium!

But, as far as I’m concerned, I would rather buy a quartz, a spinel or a beautiful tourmaline, than a synthetic gem… Something that stems from nature… Diamonds make people dream, but the latter show a true lack of knowledge regarding this product. I would say that what matters is to sell the gems for what they really are.

In my opinion, the problem lies in the fact that traders are not 100% in control of their supply. But they are not supposed to sell synthetics to top jewelers in a batch of melees! What is at stake for the top Houses is unthinkable: their credibility and their public image. Of course, they do not submit a 4C appraisal report to their clients. But they take all possible steps to ensure the quality and traceability of the gems at all levels. Their name is enough to guarantee the value and the quality of the jewel.

The greatest risks reside in the appraisal of the melee batches. This is why we are currently designing and developing new advanced tools in order to appraise them. Our research should lead to concrete results by the end of January…

Picture P.Aronin and LFG