In a nut shell, a diamond grading certificate (or "Diamond certificate") is a report drafted by an independent gemological laboratory. In this report many variants regarding the diamond are described, this allows an overall assessment of the diamonds quality. |
There are no two diamonds exactly alike. A diamond certificate will provide a list of a specific diamond's unique characteristics. The most basic of these are, of course, the famous four C's - Color, Clarity, Carat weight and Cut. A diamond's certificate will also include a hand drawn diagram showing the stones measurements, relative proportions, location and size of any inclusions and much more. Since each diamond is unique it is usually self apparent that the diamond certificate associated with it is indeed the one drawn out for this specific stone.
Gemology Institutes which Issue Diamond Certificates There is no shortage of gemology laboratories (or at least businesses which bestow this title onto themselves) . Many such institutions offer a service of issuing diamond certificates. However, in the diamond trade only certificates by a few well know institutions are truly respected. Among these institutions is the EGL (European Gemological Laboratories), GIA (Gemological Institute of America), the Belgian HRD (Hoge Raad voor Diamant or Diamond high council) and DGI (Diamond Gemological Institute) located in the Israeli diamond exchange complex.
Some Common Terms used in Diamond Certificates To better understand a diamond certificate it is a good idea to acquaint one's self with the terms commonly used in them: - A diamonds ID is a unique number associated with a particular diamond. It may be etched by laser on the diamonds girdle (Dia-script).
-Cut, Shape, dimensions and proportions all have to do with the type of the cut (such as the heart, the marquise, pear shaped, emerald cut, princess cut and radiant cut) and measurements of relevant shapes (such as largest diameter, lengths, depths, widths etc.). Some measurements are given as a percentage of others (mainly of the diamonds girdle which is the stones widest part).
-Carat is the standard unit used to express diamonds' weights . One carat is 200 milligrams (or 0.2 grams). -Graining reflects irregularities in the crystal structure.
-Cutlet, the point at the bottom of the diamond. The cutlet may be faceted in which case data regarding the symmetry and dimensions of the cutlet's facets will be brought.
Other variants described in a diamond certificate will be finish, polish, symmetry, clarity, color, pavilion depth, Tolkowsky ideal cut, florescence, Crown height and more.
A professional diamond certificate issued by a high standard gemological institution, such as DGI, will contain a key to symbols which makes it easier to understand the data depicted in the certificate. A diamond certificate from a leading gemological laboratory, such as DIG, is the way to ensure the diamond you buy is truly of the quality promised.
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