Diamond Cut Grade

 A diamond grading report with a diamond cut grade is essential when you want a full evaluation of a diamond's quality. AGS Laboratories takes the diamond cut grade a step beyond other grading reports. The AGS Laboratories analyzes a diamond's light performance in both the quantity and quality of the light being returned to the viewer. To do this, we first measure the diamond in three dimensions, then use a powerful software program to trace the light traveling through the diamond. Once this has been done an AGS Laboratories diamond grader will analyze the diamond under a microscope for polish and symmetry.

The following are descriptions for the American Gem Society Diamond Cut Grades.

AGS Ideal^® Cut — Superior craftsmanship in the diamond cutting process. All diamond cut quality factors are at the highest possible levels, and they make the maximum contribution to the diamond’s beauty and value.

1 Cut — A diamond's cut describes a very high level of expertise on the part of the cutter. There are very slight variations in one or more of the diamond cut quality factors, but these can be detected only by computer analysis or by a trained AGS Laboratories diamond grader working under controlled conditions.

2 Cut — This describes a high level of diamond cutting expertise. There are slight variations in one or more diamond cut quality factors that can be detected by computer analysis or by a trained AGS Laboratories diamond grader.

3 & 4 Cut — Minor variations in one or more diamond cut quality factors can be detected by computer analysis or by a trained AGS Laboratories diamond grader. These variations may have a slight effect on the diamond’s beauty, durability, or size appearance. You may notice differences in appearance if careful side-by-side comparisons are made to diamonds of higher diamond cut grades.

5 to 7 Cut — Sizable variations in one or more diamond cut quality factors can be detected by computer analysis or by a trained AGS Laboratories diamond grader. These variations have little effect (in grade 5) to a noticeable effect (in grade 7) on the diamond’s beauty, durability, or size appearance. You are likely to notice a less attractive appearance in diamonds that grade 5, 6, or 7 due to light performance.

8 to 10 Cut — Major variations in one or more diamond cut quality factors have significant (8) to serious (10) negative effects on the diamond’s beauty, durability, or size appearance. You almost certainly will notice poor light performance in many diamonds in these diamond cut grades.

To learn more about the American Gem Society Cut Grading System, view any of the following topics:
The AGS 0-10 Grading System
Diamond Color Grade
Diamond Clarity Grade
Glossary
Research and Technology
Performance Cut Grade System