Of the four major determining factors of a diamond, the cut is the only one that does not have an influence from nature. Thus, it is considered the most important of the 4 Cs by many due to this fact. The cut simply refers to the quality of the diamond’s cut and how well the stone is faceted, proportioned and polished. On top of that, the cut also determines how the diamond interacts with the light. The brilliance is the diamond’s ability to return light to the eye. This measurement is solely due to the stone’s cut. The color or clarity have no role in this.

So when it comes to considering a diamond, the cut should be the first factor to consider, not the shape or size. The clarity is actually the last factor you should look into. As long as there are no visible imperfections, you are fine. A beautifully finished diamond is dazzling thing to look at. Every facet is displaying the craftsman’s skill and care with the diamond. When a diamond interacts with light, every angle and every facet affects the amount of light returned to the eye. This is what gives it its face-up appearance and appeal and makes the price point higher than others.

Diamond Cut Grades

When it comes to the cut of a diamond, there are grades that the GIA gives them. These grades for cuts are excellent, very good, good, fair, and poor. The grade of the cut does not influence the price of the diamond as much as you’d think, despite it being the first factor of considering. When you stick to Excellent and Very Good cuts, you will be getting a well-cut stone that interacts great with light.

A good rule of thumb to follow is the higher the cut grade, the brighter the diamond is. Under fluorescent lighting, some diamonds can display either high, moderate, or low brightness. The term “cut” also describes a fashioned diamond’s shape. What this means is that shapes other than the standard round brilliant are called fancy cuts. Some of these cuts even have their own names. The best known cuts are the marquise, princess, pear, oval, heart, and emerald cut.

Cut Grading System Evaluation Components

There are seven components that make up the GIA Cut Grading System for a standard round brilliant diamond. The seven components are brightness, fire, and scintillation, weight ratio, durability, polish, and symmetry. Brightness, fire, and scintillation look at the diamond’s overall face-up appearance and grade it. Weight ratio, durability, polish, and symmetry all assess a diamond’s design and craftsmanship. Let’s take a closer look at these components.


The brightness is the internal and external white light that reflects from a diamond. In general, it is the arrangement of light and dark areas that results from internal and external reflections.


The scattering of white light into all the colors of the rainbow. Also determines the relief of light and dark areas that creates the face-up pattern of a diamond.


The scintillation is the sparkle a diamond produces and the pattern of light and dark areas caused by reflections within the diamond. Overall, scintillation is the small areas of light in a polished diamond that flash on and off as the diamond, observer, or lighting moves. There are also negative scintillation effects, which includes windowing, dark centers, and dark upper girdles.

Weight Ratio

This is the comparison of a diamond’s weight to its diameter.


The durability of a diamond cover thin girdles, as well as inclusions that may weaken it.


The symmetry of a diamond refers to the outline of the stone, facet arrangement, pointing, and table.


This factor determines the overall quality of the stone’s polish, as well as takes into consideration any scratches, nicks, chips, etc.

There are many different diamond cuts that come with various grades and price points. Knowing what you want will make the decision making process easier.

In general, a diamond’s proportions will determine how light performs when it enters the diamond. If the light enters through the crown and goes out through the pavilion, then the diamond will look darker and unattractive. Losing that brightness that attracts people to a diamond in the first place. Diamonds with different proportions and good polish make better use of the light. They will be brighter, more colorful, and scintillating. All components under the GIA grading system for cuts. Learn more about the evaluation of diamond cuts and how they impact the price point.

Contact Us Today

Lieber & Solow has years of experience working in the diamond industry. Learn more about diamonds and the factors that drive up their pricing. Most notably, the 4Cs, which after the cut are color, clarity and carat. For more information about all that we do, please give us a call. The number for our office is 212-354-4060. We are a trusted supplier of diamonds and will properly appraise and sell the diamonds. So please, do not hesitate to give us a call and learn more about all of our services.