The Foundry Journal

By Category: Style Guide Articles

The Foundry Journal

More Than Just A Circle: Diamond Shapes and Cuts

In the News

Style Guide

More Than Just A Circle: Diamond Shapes and Cuts

Diamond Industry

More Than Just A Circle: Diamond Shapes and Cuts

July 13, 2015 BY Alon Ben-Shoshan IN Style Guide

While diamonds can be cut in many different shapes, each has its own unique traits. Understanding the most common diamond shapes can help you make an informed decision about what kind of diamond you wish to purchase.

Click on a Shape to Learn More

Antique Cuts

Standard Cuts

Diamonds come in a wide range of shapes, each with distinct characteristics that influence the look of your engagement ring. With so many options available you are sure to find a diamond that perfectly matches your unique style.


Round – This is the most common shape for modern diamonds. The modern round brilliant diamond has 57 facets, 58 if the culet is faceted. The proportions of the modern round brilliant were developed by Marcel Tolkowsky and published in his 1919 book Diamond Design.

Before the brilliant cut, round stones were cut in a variety of ways, as cutters experimented with facet positioning and shape. The European cut had been very popular in the 19th century. It featured a high crown and a small table, as well as a deep pavilion and a large culet facet. This resulted in a diamond with less brilliance but more fire.

After much study and calculation, Tolkowsky arrived at a design that balanced the fire of the older cut with a never-before-seen level of brilliance and light return. Both the crown and pavilion are shallower, the table is larger, and the lower bezel facets extend further down the pavilion. Because of the incredible mathematical precision that guides the facet pattern for the modern round brilliant, it is the only stone that can be given a cut grade. The grade reflects how closely the stone conforms to the pre-determined ideal. Learn more about the anatomy of a modern round brilliant here.


Princess – The design of the Princess cut was developed in the 1960’s and quickly became one of the most popular cuts, after the round brilliant. The princess cut is a clean, crisp square cut with a pavilion intended to reflect light from the central point. Unlike the Emerald or Cushion cut, the Princess has sharp corners that are not beveled or rounded. We highly recommend that Princess cuts be worn in a setting that protects the points of their delicate corners. Diamonds may be incredibly hard, but they can chip if an exposed corner is struck at the wrong angle.

Diamond cutters are constantly experimenting with the proportions and faceting arrangements for the princess cut. Each iteration produces different light effects and ultimately, the value of each combination is a matter of personal taste. The Gemological Institute of America (GIA) has stated that there is not enough industry consensus or empirical data to specify cut grading standards for Princess cut diamonds and to do so is at the risk of consumers who may be deceived by diamonds accompanied by unqualified Ideal or Excellent cut grades.


Oval – The oval cut is an elongated version of the round brilliant cut. It has very similar fire and brilliance, but has a slender outline which can make the finger it rests upon looks slender as well. Oval shapes are great for people who are looking for a slight twist on a traditional classic.
Recently we have seen innovative jewelers setting ovals in an East-West orientation on the finger. The results are very attractive and fashion forward. Much like radiant and cushion cuts, there is some debate over the best length to width ratio. The most common range is between 1:1.3 to 1:1.5  Anything thinner than that starts to look stretched and runs the risk of developing a bow-tie shaped shadow across the middle of the stone.


Marquise – This shape is also called a navette. It has a brilliant faceting pattern on the table and crown. According to legend the first of its kind was originally commissioned by the French King Louis XIV in honor of the perfectly shaped mouth of his mistress the Marquise de Pompadour. The long shape of a navette can make a smaller diamond look larger, and make the finger that it sits upon look slender and elegant.

The Marquise shape results in a proportionately larger crown-to-carat ratio than most other stones, making it a smart choice for people looking for a lot of sparkle for good value. When comparing Marquise diamonds, pay special attention to the outline and symmetry of all four quadrants of the stone. It is very easy to overlook a bulging or flattened curve which – once you notice it – will distract the eye every time you see it. Only purchase a Marquise stone with excellent symmetry. Like most stones, ideal length to width ratios are a matter of taste.

Most people prefer a Marquise ratio near 1:1.95. Anything below 1.75 starts to look squashed, and anything beyond 2.15 looks stretched. The marquise cut is susceptible to developing a bow-tie shadow if the faceting arrangements are misaligned. Set your marquise diamond in a way that will protect it’s delicate points. We recommend a v-tip setting.


Heart – The earliest mention of a heart-cut stone was made in a letter written in 1463 by the Duke of Milan, Galeazzo Maria Sforza (1444-1476). In the letter he referred to a heart-cut stone owned by Cosimo de Medici. It is believed that the heart shaped cut was developed by a diamond cutter called Lodewyk (Louis) van Berquem, who also created the diamond polishing wheel. In 1458 Louis Van Berquem discovered that diamonds could be cut by their own dust and he also introduced the idea of absolute symmetry of facets. In 1562 Mary Queen of Scots is known to have sent Queen Elizabeth I a gold ring with a “diamond made like a heart”.


Emerald –  The faceting pattern on an emerald cut was originally developed to highlight and enhance the deep green of emeralds. When the same pattern is applied to diamonds, the reflections within the stone produce a hall of mirrors effect that recedes into the heart of the stone.

Emerald cuts are not nearly as brilliant as radiants (which is why the Asscher brothers sought to improve the cut) but they make up for it in luster which gives them a cool elegance. Due to their large window-like tables and unforgiving reflections, inclusions will be clearly visible within emerald cuts. As a result, only material with very high clarity is cut into an emerald shape. Most people prefer a ratio of around 1:1.5. Anything below a 1.3 and the shape starts to look like a badly proportioned square. If you are interested in a square diamond but would like a bit more punch, take a look at the Asscher.


Pear – The pear shaped diamond is the clever combination of a round brilliant on the bottom and a marquise cut diamond on the top. Like the oval shaped diamond, keep an eye out for a bow tie shaped shadow that can sometimes hover around the middle or waist of the stone. Also pay special attention to the symmetry of pear shaped stones. They should have a smoothly rounded bottom, full curved sides and an evenly tapering point.

Some people prefer their pear shapes more plump, some prefer them slender. The general consensus is that they should be somewhere between 1:1.4 to 1:1.7. Whatever ratio you prefer, make sure that you wear your pear shaped diamond in a setting that protects it’s delicate point. We recommend a V-tip setting. Pear shapes are traditionally worn with the point towards the hand and the rounded half towards the fingertips.

Note: A slightly different cutting style called a French Tip gives that delicate point a little more heft.


Asscher – This cut has a very interesting history. It was developed in Holland in 1902 by the Asscher brothers. The design was meant to be an improvement on the emerald cut, which is often criticised for not showing enough brilliance. The Asscher brothers achieved this by giving their stones larger step facets, a smaller table and a higher crown. The resulting optical effect is reminiscent to a rippling pond, with concentric rings of light receding into infinity.

The classic Asscher cut diamond is a square but they are often found in slightly rectangular shapes as well. Any ratio of 1.05 or less will appear square to the naked eye. Depending on how much corner point has been cropped off your Asscher diamond, it may look more square or more octagonal. Choose a setting that either disguises or highlights the corners as suits your taste.

Cushion – Cushion refers to a diamond with either square or rectangular proportions, rounded corners and brilliant cut crown. The pavilion of a cushion can be faceted into any number of configurations. There is much more variation in faceting patterns for cushions than there is for round brilliant diamond. Each faceting arrangement produce a slightly different effect when viewed from the top. Ultimately the value of each style is a matter of taste.

The cushion cut is descended from an antique style of cut called an Old Mine Cut. (discussed below) Today’s cushion cut is a very pleasing blend of an antique, romantic shape, but with modern light performance. Cushions look great with square proportions, and great as a rectangle as well. Many people feel that the ideal length to width ratio is somewhere between 1:1.15 to around 1:1.20. If the rectangle’s proportions are too extreme the diamond can look stretched. If they are too close to square, but not exactly square the diamond can look misshapen. Here is a chart to help you make sense of length to width ratios.

The Cushion Brilliant – This is a variation on the original cushion cut. It appears much like the Round Brilliant, but with a more square outline. Notice how the facets on the pavilion are very long and sharp as opposed to the pavilion pattern in the first example.

The Cushion Modified Brilliant – This pavilion pattern has an extra row of facets at the top. This gives the light within the stone a “crushed ice” appearance.


Trillion – Also known as the Trilliant and the Trielle, it was designed in 1962 by the Henry Meyer Diamond Company. The triangular brilliant has a total of 31 facets and can have straight or slightly curved sides. (pictured here) The version with curved sides is used to cut larger diamonds which will be center stones in a group or as a solitaire.
Trillions with straight sides are used as accent stones. This is because smaller stones need a more distinct outline so that the human eye sees them as a triangle, not a misshapen round stone. The ideal length to width ratio of a trillion is 1:1. Trillions look particularly attractive when paired with a radiant cut center stone.


Baguette – Typically, baguettes are used today as accent stones with an emerald center gem. They are a long rectangular table cut – meaning that they are designed to show more luster than brilliance or fire. In a table cut or step cut, the facets run the entire length or width of the stone.

This cut was refined in the 1920’s and 1930’s and was very popular and much used for it’s clean lines during the Deco period. In the 16th and 17th centuries a form of baguettes called hogbacks were used to make letters and shapes in very ornate jewelry for royalty and the church.

Tapered baguettes have one end thinner than the other. Despite what you might think, baguettes are not named after the french bread. The word “baguette” actually means rod or wand, so the diamond and the bread get their names from the same place. If you are choosing baguettes as accent stones for a ring, pay attention to the color and the table size of your pairs or groups – especially if they are next to one another. If one stone has noticeably different color or a much larger or smaller table facet your eye will notice as the light reflects off of the surfaces as the ring moves.


Radiant-In many ways the Radiant cut is a blend of the princess and the cushion cut. It has a square or rectangular outline, with a brilliant faceting pattern on both the crown and pavilion. This creates a bright fiery sparkle that is popular with diamond connoisseurs.

A square radiant can look much like a princess cut, but with cropped corners. When the length to width ratio is closer to 1:1.35 a radiant can look beautifully elegant and refined. Keep an eye out for a bow-tie shaped shadow in the middle of the more elongated radiant cuts. It doesn’t appear in all stones, and is less common in radiants than in ovals, marquise or pear shapes, but it is possible.

Antique Cuts

European Cut – As bruting techniques improved it became easier to give diamonds an even round outline. Soon diamond cutters were favoring a faceting pattern that came to be known as a European Cut.

It features a round outline, reasonable symmetry, octagonal table facets, a high crown and short pavilion bezel facets. It had a shallower pavilion than the old mine cut which came before it, but a deeper pavilion than the modern round brilliant which would come after it.

Like the Old Mine Cut, it has an open culet. Occasionally the term ‘Old European Cut’ is used to mean all somewhat round brilliants predating the modern Round Brilliant, even the completely unsymmetrical ones which were fashioned in the 18th century. Tragically, many of the European cut diamonds were recut into modern round brilliants in an attempt to make them appealing to modern audiences. Now that modern round brilliants have become so ubiquitous and heirloom cuts so rare, their value has increased dramatically, causing some diamond manufacturers to begin fashioning new stones in the antique styles again.

Old Mine Cut – The old mine cut has its earliest origins in the 1730’s but is most common in Victorian, Georgian and Edwardian jewelry made in the 19th century.

Stone cutters were cleaning up damaged or misshapen table cuts by rounding out chipped corners into a cushion shape. The image of the faceting pattern seen to the left represents an ideal. In reality many of the diamonds from this era are not nearly this symmetrical or precise. You will notice from the side view that the old mine cut is much taller than its modern descendant, the cushion cut. This was both to retain weight and because the high crown and small table gave the diamond more fire.

You may also notice the pronounced culet facet. At the time it was considered attractive to have a culet clearly visible from the top of the stone. If you are a connoisseur of antique stones you probably know that it is rare to find them in color grades above J, and very rare to find them with perfectly aligned and proportioned facets. This is because these stones were cut by hand, without the assistance of electricity or digital machines which guided the cutting and polishing. Tragically, many of these historic cuts were repolished into modern cushion cuts, costing them a bit of carat weight but more importantly destroying their historical significance and unique handcrafted appeal.

Rose Cut – Due to rose cuts great surface sparkle and versatile shape, they have become very popular with the more artistic jewelers these days. It seems fashion has come full circle.

Rose cuts have been used in a variety of creative ways since they arrived on the scene in the 16th century. They started as simple, six faceted pyramids, but evolved to have 12, 18 and then 24 triangular facets. Because they have a flat base and therefore lack a pavilion that would reflect light from underneath the stone they were often given a backing of silver foil to improve their presence and light performance.

Contact us

Please leave this field empty.

We look forward to hearing from you. If you would like to speak by phone, please leave a call-back number in your message.

Create an account

Receive member pricing, track orders, etc.

Please enter corrent email

Reset your password

Enter your email address below and we'll send you a new password.

Please enter corrent email

Save and share your favorite jewelry, please sign in:

By proceeding, you agree to our
Terms & Conditions.