The cut is one of the most important characteristics of a diamond that is used to determine its quality. It refers to the facet proportion, symmetry, and polish of the gemstone. The light performance of a diamond is then determined based on all these factors.
Of course, a poor cut exhibits poor light performance making the diamond dull, while an ideal cut offers incredible light performance making the gemstone extremely brilliant. So, it is important for every consumer to learn about the ways to determine the quality of the diamond cut that they choose.
How to Determine the Quality of a Diamond Cut
One of the easiest and quickest ways to figure out the diamond cut quality is to look at its cut grade on the diamond certificate. The cut grade of a diamond is usually categorized into Excellent, Very Good, Good, Fair, and Poor. Note that the cut quality scales and grade name may vary with different diamond certification agencies.
The main factor that represents the diamond cut quality is the brilliance of the gemstone. The cuts that are crafted to enhance the sparkle of a diamond include the brilliant cut variants such round brilliant cut, radiant cut, princess cut, cushion cut, etc.
Round brilliant is regarded as the best diamond cut so far. You can determine the diamond cut quality by comparing the brilliance of two diamonds that have all other characteristics in common. The stone with better brilliance is likely to be of higher cut quality. However, this method is applicable to brilliant cut diamonds only.
If you want to analyze the diamond cut quality of step cut diamonds like an emerald cut, baguette cut, or Asscher cut diamond, it is better to evaluate the proportions and dimensions of their facets. For this, you must be familiar with key factors such as the diamond girdle, culet, table percentage, depth percentage, etc. These measurements may vary with different diamond cuts.
- The girdle of a diamond refers to its outer edge and is usually expressed in percentage. For an ideal cut diamond, the girdle percentage will range from slightly thin to thin.
- The culet refers to the bottom-most facet of a diamond. An ideal cut will have a small or very small culet. However, some diamonds will be devoid of culets as well.
- The table is defined as the top-most facet of a diamond. The table percentage is measured by dividing the depth or width of the table with that of the girdle.
- Depth percentage of a diamond is calculated by dividing the distance between the table and bottom of a diamond with its girdle width or diameter.