A diamond certificate or grading report is produced by an independent, gemological laboratory prior to the diamond being mounted, thus resulting in a very accurate, complete, unbiased grading of the stone. Certification is the most important thing the consumer should insist upon having when purchasing a diamond.
The importance of certification
Buying a diamond is very much a "blind purchase" by the consumer. It is beyond the ability of the consumer to determine the exact color grade, clarity grade, cut grade, or carat weight. Whether the diamond has been treated to enhance the color or clarity is also beyond the customer's ability to detect, but all of these factors do have a significant impact on the value, the beauty, and even on the durability of the diamond you buy. Purchasing a diamond with a certificate from a respected laboratory is the best way for the consumer to protect himself from buying a misrepresented, overgraded, treated, or problem stone.
Laboratories producing certification
- Gemological Institute of America (GIA)
The preeminent, gemological laboratory in the world is the Gem Trade Laboratory of the Gemological Institute of America. GIA, which is a non-profit, educational institution founded in the 1940s, developed the color and clarity grading systems which are used throughout the world today. GIA is recognized throughout the diamond industry for their unbiased integrity and their strict, comprehensive grading standards as seen in every grading report they produce.
- American Gem Society (AGS)
Although AGS certificates are not as prevalent in the industry, they do hold a similar recognition and respect thoughout the world to that of GIA certificates. The American Gem Society was established in 1934 as a trade organization whose purpose was to promote high standards of business ethics and encourage gemological education.
- Other laboratories
There are many other laboratories in this country and abroad producing diamond certification, but none with the same industry respect and recognition as GIA or AGS. Although most of these other laboratories use the same color and clarity grading terminology that was developed by the GIA, very few adhere to the same high standards of grading that are found in GIA and AGS reports. The consumer should be aware that many of these other certificates are designed to look like a GIA certificate and many of these other laboratories have names and initials very similar to GIA (such as IGI). It is an indisputable fact that no other laboratory has the same industry respect and international recognition as that of GIA or AGS and that diamonds with all other laboratory certificates trade for significantly less on the wholesale market. It is the opinion of Gemological Services that any jeweler who provides certification from laboratories other than GIA or AGS is doing so primarily to enhance profit margins rather than providing a legitimate service to their customers.
What a certificate is not
A certificate is a grading report, not an appraisal. Therefore, GIA and AGS certificates will not have a dollar value for the diamond as part of the report. Providing that the diamond is not damaged, the grading will not change over time; but the dollar value will change with market fluctuations. Most certificates from laboratories other than GIA or AGS have a dollar value that is prominently displayed and is most often very inflated with no relation to actual selling prices in the market. These certificates with inflated values are typically used by the jeweler as a sales tool to give the appearance that the discounted price being charged is at a much better value than it actually is.
Gemological Services provides GIA certification on all diamonds over .30 carat in size. Diamonds from .30 to .99 will have a Dossier Grading Report from GIA and will have the certificate number laser inscribed on the diamond. Diamonds weighing 1.00 carat or larger will have a full-size certificate from GIA. In addition, Gemological Services provides two copies of an appraisal document with each diamond purchase so that insurance coverage may be obtained.