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4 C's
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Diamond Certificate
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Diamond Certificate

How important is a diamond certificate? Ask yourself this: Would you buy a car that had no warranty, no service record, and a missing serial number? Of course not. Yet many people make the foolish mistake of taking the seller's word on the quality of a diamond.

What is a Diamond Grading Certificate?
Simply put, a diamond certificate is a complete evaluation of your diamond that has been performed by a qualified professional with the help of special gemological instruments. As you probably know, every diamond, like every fingerprint, is unique and distinguishable from every other. Each stone bears its own recognizable, individual characteristics. The certificate will map out all this information about your diamond in a picture--sort of like a photo ID.

Properly speaking, a gemological laboratory issues a diamond grading report, not a certificate. Since a grading report is a statement of opinion, its value depends largely on whose opinion it is.

Who Issues Diamond Grading Reports?
There are quite a few institutions worldwide that issue diamond grading reports. To avoid a conflict of interest, the best of these organizations are not involved in the buying, selling, or appraising of gems or jewelry. The blue-chip standard of diamond grading reports is issued by the Gemological Institute of America, or GIA. The leading diamond report that includes a cut grade is the Diamond Quality Document from the American Gem Society Gemological Laboratories.

These organizations not only refrain from direct involvement in the diamond trade, they also act as research and educational facilities. The GIA, for instance, is also an academy for obtaining a gemologist's degree, and others are actively involved in the study of diamond and gem science. The impartial information that comes out of these laboratories is a crucial tool for gem traders and retailers, and in fact is often used to settle disputes or controversies in the gem industry.

If you've never heard of the institution that is offering a grading report, don't hesitate to ask about its credentials. But don't expect the grades from an unknown laboratory to be the same as a GIA or AGS report. Not all labs are as strict, so you aren't comparing apples to apples. In fact, some labs are popular with retailers because they have a reputation of being generous with grades.

What's on a Diamond Grading Report?
Basically the grading report confirms information about the Four Cs. It lists the color grade, the clarity grade, the size of the diamond within 0.1 carat, and cut information. Not all labs grade cutting quality. The GIA just provides some general measurements and then provides an evaluation of symmetry and polish. AGS uses a grading scale from 0 (best) to 10 (worst).

A grading report also includes a map of the diamond's inclusions, which acts as an identification. You can always compare any diamond to its certificate by examining the diamond under a 10x loupe.

Finally, the grading report will include comments about a diamond's fluorescence, girdle thickness, and culet size, which are less important than the Four Cs but are still factors that can affect a diamond's brilliance and value.

Please note: a grading report does not include an appraisal, or any kind of statement about the monetary worth of the diamond. Grading reports only stick to facts that can be scientifically evaluated, or at least judged by highly standardized criteria.

How do I get a Grading Report?
All you have to do is ask for one. It's as simple as that. The world's top jewelers and auction houses routinely give grading reports with important diamonds. Mondera.com provides a grading report from GIA or AGS with every diamond we sell. Why shouldn't you expect the same from any retailer?

Remember, the first rule of buying jewelry is to buy from someone you trust. The second is to be sure you've gotten what you paid for. A grading report from a qualified laboratory will give you this reassurance.