Diamond cut is part of the 4Cs and influences the reflection, brilliance and sparkle of your diamond – and therefore plays a big role in determining the value of cut diamonds.
The cut grade takes a few different elements into consideration such as proportions, polish, shape and symmetry of the cut diamonds. These factors influence the way light is reflected when it enters the diamond and exits from the table. The better the cut diamonds grade, the more sparkle and brilliance the diamond has making it all the more stunning.
With a good cut, the light that enters the diamond through the table travels to the pavilion where it reflected to the table. The angle at which the light is reflected determines the brightness of that iconic diamond spark. Therefore, diamond cut is a critical part of what makes your diamond come to life when you’re wearing it as jewelry.
Types of diamond cut
- Round – An excellent cutting grade with measurement depth and width was needed to bring brilliance to the diamond. About 75 percent of cut diamonds in the market are round cut diamonds. The reason behind popularity is with the brilliance round cut diamonds could offer. The brilliance of round cut diamonds are from the total internal reflection mechanics of its facets, which allows maximum light reflected to the table. Most round cut diamonds have 58 facets, some may possess 57 facets if it does not have a culet (small facet at the point of round cut diamonds);
- Cushion – Cushion cut diamonds was shaped like a square with rounded circles and a length-to-width ratio of 1.00. However, the most popular cut diamonds shape was slightly rectangle with a length-to-width ratio ranging between 1.10 and 1.20; Cushion Cut is ideal for color diamonds as it maximize the color;
- Oval – Oval cut diamonds shape has 56 to 58 facets with an elongated round shape and an excellent bowtie effect. That’s the reason an oval shape diamond gives the illusion that they look slightly bigger in size than round cut diamonds on engagement rings, given the carat weight is the same. The depth ratio is different to round, also thinner in width;
- Asscher – Asscher cut diamonds was developed by Joseph Asscher in 1902 and was the first signature cut to be patented. In 1908, his company was commissioned by the Royal Family to cut the world’s largest diamond in history, the 3.106ct Cullinan diamond. These diamonds were cut to a 74 facet step-cut octagon, with a majesty and sophistication depth all of their own, embodying the elegance of an earlier age;
- Princess – Princess cut diamonds are the second most sought in the world. It comes second in popularity to round cut. The princess cut have a square shape, the identical square shape makes princess cut diamonds popular among people who are looking for a ring, it would be an excellent choice for clean and neat designs:
- Emerald – The emerald cut diamonds came with step cuts, meaning it has a row of facets that resemble the steps of a staircase and is usually four-sided and elongated. Because of its long and width lines, the visual would be generally less fiery than Round Brilliant Cut diamonds, yet they tend to have much wider dramatic flashes of light with depth makes it ideal for color diamonds.
- Marquise – Though marquise cut diamonds are not as famous as round cut diamonds, it could be an excellent option if you are looking for an elongated shape diamond ring. As its longer and narrower in width than the round cut, it will look significant in a face-up position;
- Pear – Pear cut diamonds are fancy cut diamonds with variation of the traditional round brilliant cut diamonds. In a sense it is a combination of Oval and Marquise cut diamonds because it has one rounded end and a tapering point, resembling the shape of a glittering teardrop. Pear Shape diamonds have good depth-width proportions that refract light as the faceting releases the natural brilliance. This cut allows a range of cutting styles so that the shape can look wider and slimmer in width, or cut to proportions based on personal preferences making them excellent for any type of jewelry;
- Heart – There is no denying the fact that heart cut diamonds are unique and an excellent symbol of love. These cut diamonds are commonly used in promise rings and in solitaire pendants. The width and depth of a heart shape is difficult to perceive in smaller diamonds. Therefore, if you are interested in buying heart-shaped diamonds it is advised that you buy at least a 2ct diamond;
- Radiant – If you are looking for cut diamonds that is brilliant with rectangular shape, the best option will be for radiant cut diamonds. Radiant cut diamonds are usually rectangular or square. Aside from width-depth ratio, the corners of radiant cut diamonds are truncated and the outline is similar to that of an emerald cut makes it an ideal cut for color diamonds. However, the brilliance of radiant cut diamonds are much better than emerald cut diamonds.
Size do matters, “more carat?” or “more brilliance”?
The important reason behind the excellent variations of cutting, is the fact diamond cutters tried their best to preserve as much of the cut diamonds crystal as possible. Diamond cutting is a critical process that gives brilliance to a rough diamond. It is understandable that more facets (not too many) reflects more brilliance to cut diamonds, in exchange the cut diamonds loose reasonable amount of its mineral (ct). This process is necessary to trim off natural inclusions of a diamond, a critical decision for a diamond cutter to keep “more carat?” or “more brilliance”.
Carat is one of the GIA 4Cs that affects the diamond value significantly. Many thinks “ct” is a size unit, but it is about weight in reality. The word “carat” comes from Carob seed used centuries ago to weight precious stones as it possess a stable and uniformed weight. An example, one full ct stone weights 200 milligrams or 0.007 ounces or 0.2 grams.
A single Ct unit could divided into 100 points in order to weight diamonds below 1ct, or to provide detailed description for diamond weight in 2nd decimal place. So, a diamond weighing half a ct is 50 points, and a diamond weighing 2ct and a quarter is a “2ct and 25 point” diamond.
In the professional diamond industry, the ct weight of a diamond is also used for diamond value. Industry professionals quote in a “price per ct” format. To reach the value of the diamond, the price per ct unit must be multiplied by the total ct weight.
Based on information at time of writing, here’s an example:
Loose diamond: 3ct VVS1 J Color
- Price / Ct: $14,190
- Total value: $42,570
Grading the diamond cut
While there are some differences between grading systems as to how a cut grade is described, there are general rules accepted as the international standards for defining diamond cut grades. To grade a stone, the basic outline will be its width-depth ratio. Depth is important to determine the brightness (reflection) of cut diamonds. If the depth is too thin, it will show a “fisheye” that is a white circle in the middle of the table. If the depth is too thick, there may be a “nail-head” which gave the stone a shade in the center.
- IDEAL CUT
This is the very best diamond cut grade a diamond can have. The brilliance is simply stunning as the light is perfectly reflected through its ideal proportions (e.g. width-depth) and symmetry. These diamonds are of maximum quality and highly valued;
- EXCELLENT CUT
While still stunning, they are not absolutely perfect in terms of symmetry and proportions (e.g. width-depth) quality. However, wearing a diamond with Excellent Cut will still have the sparkle we all expect from a brilliant diamond;
- VERY GOOD CUT
Diamonds of this cut grade are a great way to balance size and quality as the brilliance (reflection) is still stunning, yet slightly below the Ideal and Excellent cut grades. The diamonds provide excellent value for buyers looking for a larger diamond in a better cost;
- GOOD CUT
When it comes to Good Cut, the diamond’s proportions and symmetry quality is slightly off from what is considered the ideal. This usually reflects the diamond cutter’s choice to maximize size when cutting a rough diamond into a polished diamond. That said, diamonds with this cut grade will still shine with brightness and sparkle;
- FAIR & POOR CUT
These are typically diamond quality where maximum ct weight was considered the most important criteria above the cut grade and light reflections. The depth and width measurements are not exactly fit for light reflection purpose. Most diamond buyers prefer to have a better cut grade for a smaller diamond to make sure what they have a diamond that has enough brilliance.
Are we clear?
One of the critical quality objective in diamond cutting is to trim out as much inclusions as possible. The diamond cutter will avoid showing any inclusions that may affect the reflection and clarity level of cut diamonds.
When the GIA grades diamonds for their diamond grading reports, diamond clarity will be defined along a scale ranging from Flawless to Imperfect. To determine, diamond experts look at various elements which in total add to the grade assigned to the diamond. This includes not only the presence of inclusions or blemishes as imperfections but also its scale, type, and locations.
When it comes to determining diamond clarity, a GIA diamond grader needs to use a 10x lens to indicate all visible spots on a faceted diamond. A flawless (FL), or Internally Flawless (IF) diamond is the rarest that means the GIA grader cannot see a single imperfection in the diamond. Most of the best quality diamonds are Very Very Sightly (VVS) or Very Sightly (VS) included, the inclusions in this grade are extremely difficult to spot even under a 10x lens by a GIA grader. Given the same ct and cutting, the value of a 3ct diamond can be significantly different between VS and VVS. The ideal range for a quality diamond is from SI to VVS, since inclusions are invisible under naked eye.
Under naked eye, one can only see the inclusions from grade SI or below. Inclusions are natural minerals formed within the diamond. It is natural to observe acceptable amount of inclusions in a diamond. Some diamond shapes may require higher clarity grade such as emerald cut, as its comparably bigger table makes it easier to expose positive inclusions. Experts consider inclusions in gemstones as part of its beauty belongs to a natural mineral, however, the content of inclusions should not be dominant or the first thing you see while looking at a diamond.
If you come along with a bracelet with 2ct round cut diamonds, which comes with D color VS quality, we can assume that this is one of the rarest and most excellent quality diamond jewelry in the world.
How to get the wholesale value for your excellent diamond?
Since 1961, the Diamond Registry has published an overview of up-to-date wholesale prices for GIA certified Emerald Cut diamonds. Buying diamonds at wholesale will get you the exact diamond you want at a much better than retail. Below you will find the wholesale value for Fancy Shape diamonds per ct, arranged by GIA clarity grade and ct weight. To get the average wholesale value for the exact diamond you want, multiply the per ct value by the number of ct you want.
What to do next
Fill in the quote form to receive a free quote for the value of your diamond. Our diamond expert will personally contact you to give all the information you need. Sourcing our global network of diamond cutters and suppliers, we can find GIA certified diamonds at the best available wholesale prices. Your diamond expert will answer any further questions you might still have. He is your dedicated contact from beginning to end.