Diamond Shape

The shape of a diamond refers to the actual appearance of the polished diamond and the physical shape it was cut into. Most rough diamonds are symmetrically formed into a hexahedral shape out of which two round brilliant diamonds can be cut with the least amount of loss. Therefore, the round brilliant is by far the most popular diamond shape, with 75% of all diamond cut into this shape.  Rough crystals that are not symmetrically formed or have awkwardly located inclusions are often cut into what is called a “fancy cut” or a cut other than a round brilliant. With the introduction of ever more advanced technologies these Fancy cuts have taken all sorts of shapes, but the majority of fancy shapes are square or rectangular (princess, baguette, Asscher, emerald, radiant), heart-shaped, pear-shaped, oval, or marquise (like a pear but pointed on both ends).

Round Brilliant Cut Diamonds

In 1919, Marcel Tolkowsky published, “Diamond Design: A Study of the Reflection and Refraction of Light in Diamond,” which explained the ideal angles for a diamond to produce the highest level of brilliance and fire. His work created a surge in the Round Brilliant Cut’s popularity, which remains consistent today. The Round Brilliant’s refined shape allows for maximum reflection of light, contributing to its incredible brilliance. Round Brilliant Cuts have 58 facets (including the culet).

Length to width ratio: For the most aesthetic diamonds, choose a length to width ratio of 1.0-1.03.

Buying tip: The cut quality of a Round Brilliant significantly impacts its beauty and is perhaps the most important element when selecting a diamond. In addition to reviewing ratings or GIA reports, look at the diamond firsthand or ask for the help of an expert.

Strong points: The Round Brilliant Cut is popular for many reasons, one being that it provides exceptional brilliance and a classic, ageless look. Round Brilliant Cut diamonds are stunning choices for engagement rings, necklaces and other fine pieces of jewelry

Princess Cut Diamonds

This fancy cut shape is second in diamond popularity after the Round Brilliant Cut. It’s created from the inverted pyramid of the rough diamond stone. Traditionally square, the Princess Cut achieves greater brilliance and fire than other similarly shaped diamonds. Rectangular Princess Cuts are also available.

Length to width ratio: A length to width ratio of 1.0-1.05 offers a square shape to the naked eye. For a rectangular Princess Cut, 1.5-2.0 is a suitable range.

Buying tip: To prevent damage to the corners, a Princess Cut Diamond should be set with prongs on all four corners. Inclusions will generally be hidden by the prongs, so it’s acceptable to choose a Princess Cut with inclusions toward the edges.

Strong points: The Princess Cut allows for a square outline while still offering nearly the same brilliance as the Round Brilliant Cut.

Emerald Cut Diamonds

Using the technique originally designed to cut emeralds, this diamond shape comes rightly by its name. With its large table surface, the Emerald Cut Diamond offers abundant reflections through its long, straight lines or ‘steps.’ Emerald Cuts are prominent in both square and rectangle.

Length to width ratio: A traditional Emerald Cut ratio ranges from 1.30 to 1.60, with the most popular choice being 1.50.

Buying tip: Because of its magnificently large table, inclusions may be more noticeable in an Emerald Cut. For this reason, seek a VS1 or VS2 for the emerald shape. Normally an SI1 has a good chance of not having any visible inclusions, but with the emerald shape there is a chance that due to reflections otherwise invisible inclusions will be visible

Strong points: Most notably, the Emerald Cut showcases size better than other diamonds of the same carat. Emerald Cuts are a premium choice for those desiring a larger piece without an enormous price tag.

Cushion Cut Diamonds

The Cushion Cut Diamond gets its name from the combination of a square shape with rounded edges, making it look like a pillow or cushion. Due to its precise bending and dispersion of light, the Cushion Cut beams with fire. Different than other diamond shapes, the Cushion Cut can be designed in many variations, including standard, modified and modern.

Length to width ratio: Cushions are often square, but can be rectangular as well. For the square shape, keep the ratio between 1.0 -1.09. Slight rectangles usually range from 1.15-1.25 in ratio. Buying tip: As a general guideline, try to stick to Cushions with a depth under 70% and a table under 70%. This will ensure brilliance and fire is maintained throughout the depth of the diamond.

Asscher Cut Diamonds

First produced by the Asscher Brothers of Amsterdam in Holland in 1902, the Asscher Cut Diamond regained popularity in 2002 after its one hundredth anniversary and a slight modification to the cut technique.
As a dazzling alternative to the Emerald Cut, the Asscher Cut Diamond hosts a smaller table and more layered facets. Brilliance is achieved through light reflection among the square facets seen underneath the table. The Asscher Cut’s trimmed corners give it extra style and stability.

Length to width ratio: A length to width ratio for a square Asscher should fall between 1.0-1.05 to maintain a square look for the naked eye.

Buying tip: When it comes to Color, Asscher Cuts don’t mask the color of the diamond’s rough material as well as other cuts like the Round Brilliant and Princess Cut. Asschers are cut for their clarity and lustre—so nothing is hidden. For this reason, we recommend buying a minimum of an H Color in the Asscher Cut.

Strong points: While similar to the Emerald Cut, the Asscher tends to offer a bit more sparkle, due to its high crown, deep pavilion and 58 facets.

Pear Shaped Diamond

With a rounded side that narrows to a distinct point, the Pear Shaped Diamond is an elegant, timeless choice. If purchasing for a ring, the pointed end will point toward the heart of the wearer. Symmetry is critical to the appearance of a Pear Shaped Diamond so it shimmers evenly.

Length to width ratio: The classic length to width ratio ranges from 1.45-1.75. Reviewing a variety of ratios will give you an idea of personal preference. You may wish, for example, for a wider or more narrow shape.

Heart Shaped Diamond

A prominent symbol of love, the Heart Shaped Diamond boasts an exquisite figure that can be set in a ring, pendant or other jewelry piece. Heart Shaped diamonds range in slenderness and width, selected primarily on personal preference. A well-cut Heart Shaped Diamond should be symmetrical, so it appears balanced and full. The point or cleft of the diamond should be distinct.

Length to width ratio: An ideal length to width ratio is 1.00. The lower the ratio, the more “chubby” the Heart will look. If the ratio is above 1.10, the Heart will appear more stretched (elongated, tall and thin).

Buying tip: Due to its form, the Heart Shaped Cut comes best in a higher carat, such as 1 or 2. If using a smaller carat weight, a three-prong setting will aid in highlighting the outline of the heart.

Strong points: The Heart Shaped Diamond requires a premium cut, prolonging and possibly increasing its value over time.

 Oval Diamonds

Showcasing similar brilliance and fire to the Round Cut, the Oval Diamond is an exquisite choice for those who wish to wear a unique shape. The Oval’s elongated silhouette offers a large appearance compared to other shapes of the same carat.

Length to width ratio: While always dependent on personal preference, the Oval Diamond is often appealing in a ratio of 1.30-1.50.

Strong points: The oval shaped diamond is durable because it carries no pointed edges. 

Radiant Cut Diamonds

Radiant Cut Diamonds gained their popularity in the 1980s due to their dazzling brilliance which is only exceeded by the Round Brilliant. The Radiant Cut is an enchanting choice due to its numerous facets found in the pavilion and crown. These features provide a high level of both brilliance and fire. Its cropped corners also make it a delightful match for pairing with rounded or square diamonds.

Length to width ratio: A 1.0-1.05 is an ideal range for a square cut. Rectangular shapes may have a ratio of up to 2.0.

Buying tip: The Color differences in Radiant Cuts are harder to perceive than in other diamond shapes. An H Color grade is usually sufficient in Radiants, allowing you to use your budget on other aspects of the cut quality.

Strong points: Radiants are formed with many facets and angles, making them appear almost like cracked ice. Because of this, flaws and inclusions are easily hidden. The beveled corners of Radiant Cuts allow for more stability—making it a wise choice for those with an active lifestyle.

Marquise Diamond

Originally requested by King Louis XIV to mimic the shape of his mistress’ mouth, the Marquise Diamond has remained a flattering and delightful choice for several centuries. The narrow body of the Marquise Diamond resembles the shape of an elongated eye. Its stunning large crown is complementary to wearers as it makes the finger appear longer and more slender.

Length to width ratio: The Marquise’s unique structure offers a length to width range of 1.85 to 2.1.

Buying tip: Due to its long shape, symmetry is important when selecting a Marquise Diamond. Ensure the two pointed ends align almost perfectly with each other. When a Marquise Diamond is set, two prongs will hold the pointed ends to prevent chipping. It’s worth noting that inclusions near the tips of the Marquise will likely be hidden by these prongs.

Strong points: The Marquise’s elongated figure gives the appearance of a larger stone when compared to other shapes in the same carat. Making the fingers of the wearer look thinner and longer, the Marquise shines brightly and is usually noticed for its unique shape.


Showcasing 24 parallel facets, the Baguette Diamond hosts long, parallel lines and remarkable clarity. Rectangular in shape with step cutting, Baguettes make for vibrant ring center pieces and graceful side stones.

Length to width ratio: Based on personal preference and use of the Baguette Diamond, length to width ratios range from 1.50-2.40.

Buying tip: Usually available in smaller sizes, the Baguette is a perfect accent to another stone or as a part of a wedding band. Several Baguettes can be placed next to each other for a large diamond array. Because of the Baguette’s clearness, ensure no noticeable inclusions are contained within the diamond.


Trillion Diamonds, also known as trilliant diamonds, are incredibly enchanting and unique. Different than round, square or rectangular shapes, the Trillion almost always makes an impression. With their rich brilliance and deep fire, Trillions diverge from popular shapes yet are just as exquisite.

Length to width ratio: The ideal length to width ratio for a Trillion is 1.0-1.10.

Buying tip: Trillions make for prominent centerpieces of an engagement ring or as complementary side stones. When setting a Trillion Diamond, ensure the edges are protected with prongs. 

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