Diamond Grading, Grades
certified diamonds it is important to understand
the diamond grading criteria used by the laboratories performing the certification.
Diamond grading covers numerous aspects of each individual diamond's qualities, but there are four
grades which are critical to understand:
- color; and
- carat weight
There are additional ratings and measurements noted on a diamond certificate, but they
generally fall under one of these four categories (the "Four Cs"). For example, measurements
such as "depth" and "table" are part of the description of the diamond's cut.
You can learn more about how diamonds are graded by reading the articles listed below.
Cut is probably the most important quality factor, and the most challenging of the four Cs to understand. The brilliance of a diamond depends heavily on its cut.
Most diamonds contain some inner flaws, or inclusions, that occur during the formation process. The visibility, number and size of these inclusions determine what is called the clarity of a diamond. Diamonds that are clear create more brilliance, and thus are more highly prized and priced.
Colorless diamonds are the most desirable since they allow the most refraction of light (sparkle). Off white diamonds absorb light, inhibiting brilliance.
A carat is the unit of weight by which a diamond is measured. Because large diamonds are found less commonly than small diamonds, the price of a diamond rises exponentionaly to its size. Read this guide to get a better understanding of what a carat is and how it affects the appearance of a diamond.
The diamond certificate, which is sometimes called a grading report, is a complete evaluation of your diamond and those certificates from respected lavoratories have been performed by a qualified professional with the help of special gemological instruments. Each stone bears its own recognizable and individual characteristics, which is listed on the certificate.