The 4 C's - Diamond Shapes and Cuts Guide 

When we talk about diamond cut, we are actually referring to two separate aspects; diamond shape and diamond craftsmanship. This article will focus on diamond shapes. For information about diamond cut quality, please see our articles diamond analytics, light performance grading and the most popular diamond shapes.

When selecting a diamond, the shape of the diamond itself is one of the most important considerations. Each of the various diamond shapes has its own unique characteristics. Like all jewelry and fashion items, the most popular diamond shapes can depend on current trends and fads. Below you will find a description of the different diamond shapes you are most likely to encounter. Currently the two most popular shapes are the round brilliant and the princess cut.

The earliest diamonds were fashioned with primitive tools at a time when it was only possible to place a few rudimentary facets on them. Because the most common diamond crystal is octahedral in shape, the easiest way to cut them was to grind down the points to form a large table on one end, a small culet on the other, and round out the corners. This resulted in the “old mine cut” diamond which was more rectangular than round. Over the years it was further refined with the addition of more facets to become the ‘old European cut’, the predecessor to the modern round brilliant.

The venerable Round Brilliant or Round Cut Diamond remains by far the most popular diamond cut of all. So much so that most the gem itself is identified by this iconic shape. It is a timeless classic that is always in style and has been for hundreds of years. Because of its symmetrical geometry, a well cut round diamond has the greatest ability of any shape to maximize light performance. The A CUT ABOVE® Round Hearts and Arrows Super Ideal Diamond, with proven optics of the highest order exemplifies the extraordinary potential of the round brilliant.

Despite its enormous popularity, the round brilliant is not for everyone. To satisfy a range of personal tastes, a wide variety of diamond shapes have been developed over the years. Diamond shapes other than round are referred to as ‘fancy shapes’. The original contour of the rough diamond often determines which fancy shape diamond will be cut, as yield is a driving factor for the diamond cutter. That is, if a given piece of rough can be cut into a certain fancy shape with a resulting size significantly greater than what could be extracted in a round, then the cutter may elect to make that choice. His calculation also depends on the current demand for the fancy shape being considered.

Below are the most popular fancy diamond shapes. Other shapes are also available and may be quite desirable for very specific applications. But the following are the diamond shapes you are most likely to see in jewelry.

Like the Round Brilliant, the Princess Cut diamond has faceting patterns that gives it sparkle and brilliance. They are usually square cut with pointed corners, although some are more rectangular in shape. Princess cut diamonds are second only to the round brilliant in their popularity. They are also priced lower than comparable Round Brilliant diamonds, which makes them an excellent choice for a shopper looking for value!

The Cushion Cut diamond is one of the diamond shapes that was very popular a century ago and has come back into fashion with today’s surge in vintage styles. It is also sometimes referred to as the “pillow-cut” and has rounded corners and large facets. Cushion cut diamonds can vary between a rectangular and square shape.

Another of the fancy shape diamonds is the elegant Emerald cut diamond. They are normally rectangular in shape and have step-cut elongated facets on the crown and pavilion, with small cut corners giving the diamond an octagonal outline. The Emerald cut diamond is very revealing of clarity features so higher clarity grades are usually seen in this shape.

The Asscher Cut diamond is nearly identical to an Emerald cut diamond. Joseph Asscher was a diamond cutter who developed and patented the Asscher cut diamond in 1902. It is a square step cut diamond with a small table and a high crown. It also has wide step facets and because of the way its cut, the Asscher has more fire and reflects light more than an Emerald cut diamond and has been gaining in popularity in recent years.

The Oval Cut diamond has brilliant faceting similar to a round diamond but it is elliptical or egg-shaped. The Oval cut has always been one of the most popular of the fancy shapes, especially as a center stone for engagement rings. Its shape can give the appearance of long and slender fingers. It’s important to watch for the “bow-tie” effect when selecting an Oval. This is a noticeable darkening in the middle of the diamond that actually resembles a bow-tie.

Like an oval with points on each end, the “football” shape of a Marquise cut diamond creates an appearance that looks larger than its carat weight would suggest. It is a brilliant cut stone with 57 facets. The shape of Marquise cut diamonds can vary greatly as the length to width ratio changes. The “bow-tie” (darkening) effect is also something to look for in this shape. Like all fancy cut diamonds, a Marquise diamonds shape is a matter of personal taste.

A Pear shape diamond is a combination of the Round and Marquise cut with one rounded end and a pointed end. It is also referred to as a “tear drop” shape. The typical Pear shape diamond is cut like a round brilliant with 58 facets. The pear shape diamond is a popular choice for diamond pendants.

The Radiant Cut diamond is a rectangular cut diamond with trimmed corners. The outline is like that of an emerald cut but it has a much different flavor as it does not have the step cuts of the emerald. A radiant looks more like a rectangular Princess cut diamond with clipped corners.

The Heart shape diamond features a brilliant style faceting arrangement and an outline with two lobes, a cleft and a point. Although the shape is the universal symbol of love, there is not a huge demand for the Heart shape diamond. The shape is not very distinct is small carat diamonds, so anything below 0.50 carats is not recommended.

The Trilliant diamond is triangular is shape with a brilliant facet arrangement. There are slight variations of this cut and it is sometimes called the trillion cut. Trilliants are popular as side stones for center diamonds with brilliant cutting styles like the princess cut.

The step cuts differ from the brilliant styles rather dramatically in terms of optical effects. Step cuts such as emerald cut and Asscher, with their long and broad facets, tend to produce fewer but bigger sparkles. Brilliant styles such as the round, princess, oval, pear, and marquise produce a great number of smaller sparkles. The resulting scintillation patterns therefore produce altogether different looks. These two broad categories offer very different options for shoppers to choose from. Which overall effect you find most appealing is a very personal aesthetic choice, not only in outline shape but in the different ‘flavors’ each presents to the eye.

The length to width ratio of fancy cut diamonds conveys an important aspect of their geometry and also can impact their light performance. Most fancy cuts like emerald cut, pear shape, and oval are longer than they are wide. Princess cuts and Asschers are almost square, so this factor is largely moot. Length to width ratio is a simple calculation; the length (in millimeters) divided by the width. A higher number indicates a more elongated shape. The length/width ratio of a marquise shape may be almost 2 – twice as long as it is wide -whereas an emerald cut or radiant might be in the neighborhood of 1.5. This factor impacts the visible outline or overall shape of the diamond and its eye appeal. A fancy diamond with a ratio out of normal ranges may also suffer from light leakage or other light performance deficits that reduce its fire and brilliancy.

As you have seen in this article, there are many beautiful diamond shapes. Each shape presents a different geometry and individual aesthetic. Step cuts have an altogether different flavor than brilliant styles. Some shapes may be more compatible with certain jewelry designs than others, and some offer more affordable pricing. So, the best diamond shape is really the one that is best for YOU.

Having said that, the goal for most shoppers is to find the most brilliant and fiery diamond they can afford. If this is your driving force, the round brilliant is the shape that offers the best potential for optimizing light performance. Ideal and super ideal cut diamonds return over 90% of the light entering their crowns back to the eye of the observer. Their mix of large and small virtual facets provides for outstanding fire and dazzling scintillation. And choices for beautiful jewelry styles abound, such as those offered by the top designer brands in the market.

At Whiteflash we specialize in ideal and super ideal round and princess cut diamonds, and we carry a large in-house inventory of fully vetted diamonds available for immediate delivery. Diamonds in our in-house categories (A CUT ABOVE®, Expert Selection, and Premium Select) are exclusive to Whiteflash and will not be found anywhere else. But we also provide customers with a full range of shapes through our Virtual Selection category which allows customers to leverage all the advantages of our expertise in light performance, and thorough vetting by our team of gemologists.

Feel free to contact us by phone, email or chat and one of the friendly and knowledgeable Whiteflash diamond consultants will help you find the diamond that is just right for YOU, whatever shape that may be.