Diamond Grading, Grades
When purchasing 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: cut, clarity, color, and carat weight. There are additional ratings and measurements noted on a diamond certificate, but they generally fall under the diamond's grade in one of the Four Cs. For example, measurements listed 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.
Diamond Cut
Cut is probably the most important quality factor, and most challenging, of the four Cs to understand. The brilliance of a diamond depends heavily on its cut. Diamond Clarity
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. Diamond Color
Colorless diamonds are the most desirable since they allow the most refraction of light (sparkle). Off white diamonds absorb light, inhibiting brilliance. Carat Weight
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 Fifth C: Certificates
The diamond certificate, which is sometimes called a grading report, is a complete evaluation of your diamond that has been performed by a qualified professional with the help of special gemological instruments. Each stone bears its own recognizable, individual characteristics, which is listed on the certificate.