CUT GRADE
1. What is Cut?
The jewelry industry refers to Cut in two ways:
1. As a reference to the shape, style and faceting of a diamond.
2. How well a diamond is fashioned (e.g., brilliance, fire and scintillation).
2. What is an Ideal Cut diamond?
There is much debate in the diamond industry about what an actual Ideal Cut is. An AGS Ideal Cut is a diamond where all of the diamond’s Cut quality factors (light performance, proportions, and polish and symmetry) are at the highest possible levels, and they make the maximum contribution to the diamond’s beauty and value.
3. What are the factors that determine a diamond’s Cut Grade?
AGS Laboratories utilizes the AGS Performance-Based Cut Grade system, which is based on the overall performance of a diamond, specifically in the area of Light Performance. When analyzing the overall performance of the diamond, we take the following into consideration: light performance (contrast, leakage, dispersion, and brightness), proportion factors (girdle thickness, Culet size, Weight Ratio, durability, and tilt) and finish (Polish and Symmetry).
4. Is there a Cut Grade for fancy shape diamonds?
Yes, in 2004, AGS released their fancy shape Cut Grade research, which concluded five years of research by a team of diamond experts, optical physicists and mathematicians. The AGS Laboratories' Diamond Quality™ Document was the first diamond grading report to ever issue a fancy shape diamond Cut grade. Currently AGS Laboratories is now grading the Princess Cut, Emerald Cut, and Oval Cut shapes, other fancy shapes will follow.
5. What is Brightness?
The amount of white light in a diamond that is returned to the observer.
6. What is Brilliance?
A diamond’s brightness with positive contrast effects.
7. What is Contrast?
The light and dark patterns seen when observing a faceted diamond. It can be positive or negative in its optical effect. Usually caused by, but not limited to, the observer's head.
8. What is Dispersion?
The separation of white light into colors by refraction in a diamond.
9. What is Durability?
A diamond’s resistance to chipping or breaking.
10. What is Leakage?
Areas in a diamond that do not return light.
11. What is Weight Ratio?
The millimeter footprint of a diamond versus its weight.
12. What is Tilt?
The point at which the girdle reflects in the table of a diamond. It is defined by the minimum pavilion angle allowed for each table size.
13. What is Luster?
Luster is the quality and quantity of light reflected from a gem's surface.
14. What is Polish?
Polish is the quality of the diamond's surface and edges.
15. What are Proportions?
Proportions are the size and angular relationships among the main parts of the diamond. AGS Laboratories diamond graders consider the following factors when evaluating Proportions: Table Size, Crown Angle, Girdle Thickness, Pavilion Angle, Culet Size.
16. What is a Culet?
A Culet is the point on the bottom of a diamond's pavilion. A diamond's Culet may be pointed or it may be blunted with a small facet.
17. What is Shape?
The Shape is the outline of the diamond such as marquise, pear, or oval.
18. What is Symmetry?
Symmetry is the exactness of the balance and evenness of the diamond's shape and facets.