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AGS Diamond Grading System

The AGS 010 Diamond Grading System

Diamond in a loupe

The AGS 0–10 grading scale is easy to understand: the highest possible grade is zero, and the lowest is 10.

Easy, huh?

So, a diamond with a color grade of 3 has less color than a diamond with a color grade of 5. Diamonds having less color are rarer; therefore, they may cost more.

When writing the grades of a diamond using the AGS Scale, diamond Cut grade is first, then diamond Color, Clarity, then Carat Weight — in that order.

If a diamond possessing the finest diamond Cut grade is also colorless, free of inclusions and blemishes, and weighs one carat, it would be written as: 0/0/0–1.000 carat.

In the American Gem Society Diamond Grading Standards, this would be known as the famed Triple Zero® or Triple 000.

Cut Scale
Cut Scale

Color Scale 
Color Scale

Clarity Scale

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