Certificate
A certificate from a respected gemological laboratory provides important information and assurance about the quality of your diamond.

Definition: A diamond certificate describes the specific characteristics of the diamond, including dimensions, carat weight, clarity and color, plus a variety of measurements and/or grades related to cut.

Which diamonds have certificates?
Not all diamonds have certificates. That's because:

  • Gemological laboratory services are expensive.
  • Diamonds sent to gemological laboratories must be 'loose', i.e., removed from their settings.
  • The evaluation process can be time-consuming….it can take several weeks if the laboratory is busy.

Though gemological laboratories will grade any diamond, typically only diamonds of greater carat weight (over 0.50 carat) and higher color, clarity, cut grades are submitted.
 

Why are certificates important?
The certificate defines the diamond's characteristics according to a very strict set of rules and standards. These measures, taken together establish the diamond's market value. Remember, small differences in quality translate into big differences in value.

The diamond certificate gives you something tangible and reliable upon which to base your purchase decision.

Are all diamond certificates the same?
Each gemological laboratory applies slightly different standards/interpretations of the diamond grading conventions. As a buyer, it's important to know which laboratories are more or less conservative in their approach.

The loose diamonds offered by eSale.etc have certificates from one of the following independent laboratories:

  • American Gemological Society (AGS)
  • Gemological Institute of America (GIA)
  • European Gemological Laboratories (EGL)
  • Professional Gem Sciences (PGS)

These are among the most reputable, trusted gemological laboratories. AGS and GIA may be slightly more conservative than the EGL, however, the differences are small and are usually reflected in the price, i.e., a diamond with a GIA or AGS certificate may cost a few percent more than an identically-graded EGL certified diamond.

At eSale-etc, we always tell you if a diamond we offer has been graded generously by the AGS, GIA, PGS, or EGL; and we price it accordingly.


This is an example of a certificate.

View sample certificates from:
GIA , AGS, EGL , PGS

What's on a diamond certificate?
Certificates from the leading laboratories contain similar information:

  • Shape and Style: diamond shape and cut, e.g., round brilliant cut
  • Dimensions: measurements of the diamond in millimeters, e.g. 6.49 - 6.51 x 3.80 is the smallest - largest diameter and the total depth of a round brilliant diamond
  • Weight: carat weight of the diamond to the nearest hundredth of a carat
  • Proportions:
    • Depth % (round diamonds): depth relative to the diameter
    • Table % (round diamonds): table facet relative to the diameter
  • Girdle: range of girdle thickness, e.g. thin to medium
  • Culet: appearance of the culet facet, e.g., very small
  • Finish:
    • Grades for polish ranging from poor to excellent
    • Grades for symmetry ranging from poor to excellent
  • Clarity: clarity of the diamond as determined under 10X magnification
  • Clarity Plot: a diagram of the approximate size, location, and type of inclusions as viewed under a microscope
  • Color: color grade, usually the GIA 'D-Z' scale
  • Fluorescence: color and strength of fluorescence when the diamond is exposed to UV light
  • Comments: additional relevant information not mentioned elsewhere in the report

What's the difference between a certificate and an appraisal?
Certificates describe the characteristics of a diamond that permit you to determine its market value. The certificate is not an appraisal.

Theoretically, an appraisal is an estimate of the diamond's market value. Retailers love to provide buyers with an appraisal that is higher than the price they are charging. It makes the customer confident that he/she is getting a good deal.

Unfortunately, such appraisals are generally meaningless. By definition, the price you pay in a store is the retail market value.

If it was worth more, you would have to pay more.