Diamond Carat with Loupe and Gia Certificate | Lisa Robin

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What is Modified Brilliant Cut Diamond?

Round diamonds, or round brilliant can be modified in shape. Learn more.

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About Round and Modified Brilliant Cut Diamonds

Round Brilliant Cut Diamonds

By far the most popular diamond shape, round diamonds are more than 50 percent of all diamonds sold. The reason for their popularity is due to their brilliant cut. This allows for optimal light reflection, resulting in a brighter and more brilliant appearance than other diamond shapes. Round diamonds are also commonly called brilliant or round brilliant cut, as they are the most common type of brilliant-cut diamonds. With 58 facets, the round brilliant diamond reflects light from the bottom and back up through the top, resulting in a stunning sparkle.

Parts Of a Round Diamond Graphic | Lisa Robin

Round Brilliant has the most diamond sparkle

Due to its facet patern and how the light refraction down through the diamond and back up through the top.

Diamond Light Refraction Based on Depth of Diamond Graphic | Lisa Robin

What are the modified brilliant cut diamond shapes?

It's important to note that the diamond shape refers to the overall geometry or form of the diamond, such as round or square, and should not be confused with the diamond cut, which pertains to its facets and proportions. Also, diamond dimensions are different from carat weight, which measures weight, not size. With that cleared up, let's delve into the world of diamond shapes!

Modified brilliant cut diamond is a variation of a brilliant cut diamond. In the last 20 years, modified brilliant cutting on the pavilion have become very popular. There is no Cut grading on Modified Brilliant Cuts on diamond certifications but symmetry and polish grades of excellent – fair are given.

When it comes to engagement rings, there are six popular diamond shapes, each with its unique appeal. Let's explore each diamond shape.

Modified Brilliant Diamond Shapes

Oval Diamonds

Currently the second most popular diamond shape, the oval is elegant and flattering on the finger.

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Pear Diamonds

Learn about the beautiful ethereal shape and how it is suited to unique engagement rings.

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Marquise Diamonds

Interesting history and remarkable brilliance, learn why marquise diamonds appear larger.

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Princess Cut Diamonds

Learn about this faceted square diamond, what to look for, its sparkle, and how popular it is.

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Cushion Cut Diamonds

Cushion cut diamonds are square or rectangular shape with rounded edges, resembling a pillow.

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Radiant Cut Diamond

Radiant cut diamonds display a high brilliance, they are a rectangular shape with truncated corners. Learn more.

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Buying a diamond engagement ring means choosing from various diamond shapes: round, square, marquise, and more. Shape refers to how a diamond appears when viewed from the front (round, square, oval, etc.). But cut, specifically how it is cut, is how the facets are arranged. For instance, the brilliant diamond cut is round with 57 or 58 facets designed to maximize sparkle.

Round diamonds can be reshaped in several different ways. The most common are oval, marquise, and pear shapes. A modified brilliant cut is a brilliant cut diamond that has been altered from the traditional round shape. All diamond shapes other than round are called fancy shapes.

Frequently Asked Questions


The only diamond shape to receive a ‘cut grade’ are round brilliant cut diamonds. A modified brilliant cut is a brilliant cut diamond that has been altered from the traditional round shape. ‘Brilliant cut’ diamonds are designed to exude the most sparkle. Step cuts feature larger, parallel facets that celebrate the clarity of the stone with more subtle flashes of light

Which diamond shape is the most sparkly?

The round brilliant diamond is the most sparkly when graded triple Excellent (GIA) or Ideal (IGI). The diamond will have the optimal cut, symmetry, and polish. Multiple lines of symmetry and 58 facets work together to reflect light within and out of the diamond, making the round brilliant the sparkliest diamond shape. Typically, round brilliant diamonds are the most expensive diamond cuts, due to three factors; their unmatched brilliance, popularity, and the amount of diamond waste generated during cutting Round brilliants are the most popular shapes.

Which Diamond Shape looks the biggest?

Due to their higher sparkle, brilliant cut diamonds can appear larger than step cut diamonds. The spread of the table makes some brilliant cut shapes appear larger than others; marquise, oval, and pear diamonds appear larger than other diamond shapes of the same carat weight.

Which diamond shape is the rarest?

It is more difficult to find some diamond shapes than others. The demand for asscher diamonds and radiant diamonds is much lower than for other diamond shapes, making them rarer than most diamond cuts. They are followed closely by marquise and hearts.

What diamond shape is the most popular?

Due to many of the reasons already stated, the round brilliant diamond continues to be the most popular diamond shape in the United States. Followed by oval diamonds, pear diamonds, emerald cut diamonds, and cushion cut diamonds.

Diamonds with loupe and tweezers | Lisa Robin
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