The ICIA 0–10 Diamond Grading System

The ICIA 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. Natural diamonds having less color are rarer; therefore, they may cost more.

When writing the grades of a diamond using the ICIA 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.

Cut Scale

Check out our interactive cut chart for diamonds to determine the diamond level quality you may have.

Color Scale

This diamond color scale shows what color each diamond can be.

Clarity Scale

This diamond clarity chart shows both a visual and numerical display of how flawless or included a diamond can present as.