The AGS 0-10 Grading System

The AGS 0-10 grading scale is easy to understand. The highest possible grade is zero. 10 is the lowest. For example, a diamond with a color grade of 3 has less color than a diamond with a color grade of 5. When writing the grades of a diamond, diamond cut grade is first, then diamond color, then diamond clarity, and then carat weight. For example, a diamond that has the finest diamond cut grade, is colorless, free of inclusions and blemishes, and one carat in weight 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.

Diamond Cut Grade
Diamond Color Grade
Diamond Clarity Grade
Glossary
Research and Technology
Performance Cut Grade System