Our diamond buyers have traded in diamonds, on a wholesale level, for over fifty combined years. There are many companies that "specialize" in finding "mistake" certificates. The price is cheap, but the value is expensive. We have never and will never deal in over-valued diamonds. We will often be the least expensive, but more importantly, will always provide the best value.
There is a fifth "C" that, while being unofficial, is still an important factor. This is certification. A diamond may have a certificate, which is a gemological report that describes its physical characteristics. This is beneficial as it removes the "human judgment factor" in the determination of the actual characteristics of the diamond. Major laboratories often employ a group of gemologists, trained specifically in the technical aspects of diamonds, that come to a consensus on the specific characteristics of a particular diamond. This assures the buyer that the diamond being purchased truly is what it is advertised as.
There are only a few major laboratories around the world, and through our extensive network we deal with most of them. The most popular labs in the United States are:
The Gemological Institute of America (GIA)
Professional Gemological Sciences (PGS)
European Gemological Laboratories (EGL)
International Gemological Institute (IGI)
Hogerand Voor Diamante (HRD)
American Gem Society (AGS)
All of the laboratories are good sources for certification and none of them sell diamonds. This leaves them un-biased in their opinions and a valuable source of information to the diamond trade. There are of course other gemological laboratories, and some of them are quite good at their analysis, but we only deal with these major, well known laboratories.
Remember, you are buying this diamond for the aesthetic pleasure that you or a loved one will receive. Look at the diamonds along with the certificates and choose the diamond you find most beautiful. The diamond that "reads" the best on a certificate, is often but not always get too caught up in the game of comparison of cut grades, specific colors, clarities, etc. Of course these are quite important, but there are many different variations that look fantastic to the naked eye, which is ultimately how you will view this diamond, so you must look at the diamond, not just a certificate, because so-called minor differences in a certificate may be quite different in appearance to the naked eye.