Diamond Certification.

Recently a customer asked a colleague for a D colour, Flawless (a term I think should be revised if all the gem labs are trying to say inclusions or clarity characteristics are not flaws), brilliant cut diamond ring in a Platinum mount. We didn't have anything, but to get the conversation going, she took out a D, VS1 (very slightly included) in Platinum. The customer looked shocked to see our "lesser quality" stone was about the same price as the D, Flawless he had seen in a previous shop.

She was confused and so was I. When I sat down and worked out from trade price lists, how much the stone should cost. We couldn't even buy the stone for a trade price for that, let alone in a Platinum mount! Something must have been wrong.

The customer was a reasonable person and I asked if they could go back and check that there hadn't been a mistake. When he came back, he had details of measurements, certificate etc. The main difference was the Lab issuing the certificate. Ours was a GIA (Gemomlogical Institute of America) and theirs was an EGL (European Gemmological Laboratory).

In the past I have been asked to compare certificates to diamonds in order to ascertain they are the same stone. Some labs have been easier to match than others. GIA and HRD (Diamond High Council of Antwerp) certificates are usually easy to match as I agree with the grading. With other labs I have found it quite difficult as the stones and certificates are very different, sometimes easily being 2 grades out ( a major difference in price). I've been grading for many years before anyone makes a comment on my abilities compared to a lab, and as a buyer I have to be right or the profits suffer.

After speaking to many brokers, suppliers and industry professionals, I have found out there is a definite hierarchy in labs and their certificates. The reasons for this are many and varied. From the amount of labs under one banner in different locations making consistency difficult to commercial reasons, if a lab grades your diamond higher, you may make more money on it, so they become popular.

The obvious front runners are GIA and HRD. They are both not-for-profit organisations, meaning they plough any left over funds into research, education and generally being better. The AGS (American Gem Society) is thought of highly in the states due to a small tightly controlled team providing consistent results. Anyone else it seems is fair game although IGI (International Gemmological Institute) seems to lead the runners up, even though they issue certificates on mounted stones often, which I don't like.

The other certification to watch out for is when a shop does their own. There is a certain high street chain in the UK that states that their Managing Director grades all their diamonds. If he was doing this for 12 shops, let alone how many they have, he wouldn't have time to manage and direct! As always, Buyer Beware, but trust is key.

Many lesser labs mean heavy discounts on the normal trade prices explaining the difference in price. If the above stone was a F, VVS1 the price would be bang on. Think about it.


Take care,
Damian