About the AGS

Because most people know little about buying diamonds, the American Gem Society came into existence - now over 70 years ago. Society members developed the precise standards still in use by the AGS for evaluating diamonds.

The 4 Cs, as they are commonly known, are: Cut, Color, Clarity, and Carat Weight.

ags certification

According to the American Gem Society, Diamond Grading Standards should evaluate three of the four value factors — cut, color, and clarity — on its own 1–10 scale.

By the AGS standards, each of the scales begins at 0 (zero) for the highest grade, and goes down to 10, the lowest.

Each of those three factors is expressed separately, along with the carat weight of the stone - the fourth factor. These standards are represented on certificates issued by the AGS.

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