Critique of the Gemological Laboratories
Gemological Institue of America – GIA
The most widely known of the labs. Upholds high standards. Instituted a cut grading system for round diamonds in 2006. Cut grading system is based on mathematical diamonds models, resulting in wide light performance variations of diamonds in the same cut category.
Rating: Acceptable upon regrade.
American Gem Society – AGS
Not as well known as GIA. Upholds high standards. For years has used a cut grading system for round diamonds based on a mathematical diamond model, an approach that often was in conflict with GIA’s research.
Rating: Acceptable upon regrade.
Professional Gem Sciences – PGSL
Chicago Laboratory. Upholds high standards. Uses the SI3 grade. One of the more advanced of all the labs in colored stone grading and analysis. Grading similar to GIA and AGS. Rating: Acceptable upon regrade.
European Gemological Laboratories – EGL
Though the EGL laboratories all share the same name, they are owned and run independently of each other. Standards vary.
EGL New York – We find grading from this laboratory to currently be lax, and stones no longer meet our grading standards. Uses the SI3 grade. Stones may be graded as many as three or more grades higher than they really are. Rating: Not acceptable – AVOID.
EGL Los Angeles – We find grading from this laboratory to currently be lax, and stones no longer meet our grading standards. Uses the SI3 grade. Stones may be graded as many as three or more grades higher than they really are. Rating: Not acceptable – AVOID.
EGL Israel – We find grading from this laboratory to currently be lax and stones no longer meet our grading standards. Uses the SI3 grade. Stones may be graded as many as three or more grades higher than they really are. Rating: Not acceptable – AVOID.
There are a large number of smaller laboratories that claim to be independent but receive “contracts” from certain larger companies. We find grading from these labs to consistently be as many as three or more grades higher than they should be. In other words, they issues grades that are favorable for their clients in order to keep these large contracts. Rating: Not acceptable – AVOID.
* * *
October, 2015 (Source: JCK Online):
GIA has invalidated 1042 grading reports issued by its lab because of hacking. The reports bear grades that were altered after its system was accessed without authorization by former employees of its database support contractor. As of Oct. 30, two people have been arrested. (The moral of the story here is to be sure you know from whom you are buying a diamond and buy from a GIA graduate gemologist who has the training to verify the information on the certificate.)
GIA has banned five Indian companies from further submissions to its grading lab alleging they inscribed diamonds with GIA report numbers not associated with those gems. No further details were released regarding the length of the scam or the number of diamonds that had been falsified.
We have received the following information from GIA:
GIA reasonably suspects that they have received diamonds that were subjected to an undisclosed temporary color treatment. The treatment is a process that temporarily masks the inherent color of a diamond which can lead to it being graded up to three grades higher. GIA has not identified the treatment process and is actively researching it.
Comment: Apparently, someone or some company has been able to temporarily raise the color of a diamond just long enough for it to be graded by the GIA lab before it returns to its original lower color state. Over 400 diamonds were caught and recalled, but it may not be known how many might have made it into the marketplace. (Customers of M. Martin and Company do not need to be concerned, as we regrade every diamond before we purchase them.)
November 2014: GIA is suspending its diamond sealing services after receiving a sealed diamond for verification that did not match the data label in the sealing packet. GIA has hired an outside investigation firm to determine how this was done and to possibly determine the source of the packet.
December, 2013: There are reports of unscrupulous companies buying GIA reports and then matching synthetic diamonds to them. In many instances, they are even engraving the synthetic diamond with the GIA logo and grading report number. Moral: Know from whom you are buying the diamond. (Source: RDR, Dec. 2013)
November, 2008: We have just received notification of a new rash of counterfeit GIA certificates surfacing in the marketplace. We understand the quality of these certificates is excellent. The certificates duplicate the specifications of actual GIA certificates so that a report check with GIA will not uncover the fraud. It is suspected that some or all of these stones are coming through internet sources. Authorities are investigating.
November, 2005: As reported in numerous jewelry trade publications, GIA has fired four graders for allegedly taking payoffs from certain unnamed cutters to increase diamond grades on GIA certificates. The investigation was instituted as the result of a lawsuit. It is unknown at this time how long this has been going on, or to the extent of the misconduct. At this time, dealers do not know whether this situation extends to hundreds, or as some think, “to many thousands” of diamonds that were sold or may still be in the pipeline. We commend GIA for taking swift and decisive action on this matter, and we hope this does not impugn the integrity of this institution. However, we feel the consumer needs to be aware of this situation. (People who purchase, or have purchased, diamonds from M. Martin and Company need not be concerned, as all diamonds we sell from any laboratory are thoroughly regraded before being offered to the customer.) I will post new information as it becomes available, although it may take years before the full ramifications of this situation are known. For more details, refer to the Wall Street Journal, Dec. 20, 2005 and March 8, 2006.
Click to proceed to our Jewelry Showcase
I hoped you have enjoyed reading our web site. If you have any questions regarding any information on this site, please call me at 312-263-4957