When discussing diamonds, the different shapes and cuts are often lumped into one category. However, they are very different. While they may have similar elements, it is important to understand the distinctions between the two. This includes knowing the size and cut style (step, mixed or brilliant) to look for in each shape.


Round

The round shape is the most popular style of diamond, comprising almost three-quarters of all diamonds sold. Its brilliance is a result of its round shape. Although other shapes can be eye-catching, none are more brilliant than this.

In 1919, Polish engineer Marcel Tolkowsky published “Diamond Design: A Study of the Reflection and Refraction of Light in a Diamond.” His work examined the relationship between diamond proportions and angles and how they affect light. He found that round diamonds were the most brilliant. After his work was published, their popularity increased.
Round

Princess

Princess

The princess style diamond is one of the most popular and extravagant cuts. It usually has either a square or inverted-pyramid shape, but can sometimes be rectangular. The princess diamond is more brilliant than other similar shapes and cuts, making it a popular choice for engagement rings.

Oval

The oval style diamond arrived in the 1960s. It is an altered version of the round brilliant diamond, making it perfect for someone who wants something similar yet unique. Its extended shape makes it appear larger than other styles of a similar size.
Oval

Marquise

Marquise

The marquise diamond is another version of the round brilliant cut. It originates from King Louis XIV of France, who requested a diamond in the shape of his mistress’ mouth. It has remained popular since, and its slender and elongated shape also make it appear larger than other diamonds of a similar size.

Pear

The pear shaped diamond is round on one end and pointed on the other. It is important to wear this diamond with its point facing the body. Symmetry is critical to assure its beauty and brilliance, and it ranges from slender to wide cuts. It is a version of the round brilliant diamond.
Pear

Cushion

Cushion

The cushion style diamond is a combination of square and round cuts. Its overall shape is square, but with round edges that resemble the outline of a cushion or pillow. An older-style diamond, the cushion emits bulky light patterns different from modern cuts. It comes in standard, modified, and modern versions.

Emerald

The emerald cut diamond mirrors the cut of an actual emerald. Steps build up from its pavilion, creating a flat, plateau-like surface at the top. Although the emerald cut is not as fiery as some of its counterparts, it emits bold flashes of light that create a stunning and distinctive pattern.
Emerald

Asscher

Asscher

The Asscher style diamond was created in 1902 and became fashionable in the 1920s. By popular demand, it has recently made a comeback – featuring a modern cut that is more brilliant than its traditional counterparts.

Radiant

The radiant diamond is truly dazzling, ranking second in brilliance only to the round brilliant diamond. Its brilliance is produced by several facets surrounding its crown and pavilion. This diamond is square-shaped and features either round or squared corners.
Radiant

Heart

Heart

The heart shaped diamond is another variation of the round brilliant cut. Symmetry is its most important feature. Both halves of the heart should be identical and have a sharp meeting point. Although it is an exquisite style, its shape is dependent on its carat size. The smaller the carat, the less distinctive the shape. The heart diamond represents love.

Trillion

The trillion shaped diamond is named for its triangular figure and is among the brilliant cuts. However, it stands out from the classic look. It can sometimes be used as a main stone but is most frequently used as an accent. It appears larger than most stones of a similar size.
Trillion

Baguette

Baguette

Like the emerald cut, the baguette shaped diamond can be square or rectangular. It is designed with 14 parallel facets arranged like steps. This can give the diamond a lower grade than some of its counterparts, making it cheap for the consumer.
Suggested length to width ratios that better suit each shape:

Shape Cut Style Length: Width Rectangle Length: Width

Square

Length: Width

Common

ROUND Brilliant 1.0:1.03
PRINCESS Mixed +1.10 1.0:1.05
CUSHION Brilliant +1.15 1.0:1.05
PEAR Brilliant 1.45:1.75
OVAL Brilliant 1.33:1.66
ASSCHER Step 1.0:1.05
EMERALD Step 1.30:1.40
RADIANT Mixed +1.10 1.0:1.05
HEART Brilliant 1.90:1.10
MARQUISE Brilliant 1.70:2.25
TRILLION Brilliant 1.0:1.10
BAGUETTE Step 1.50:2.40

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