Diamond Cut

One of the most defining characteristics of a diamond is its cut. Diamond cut is the summary of a diamond's proportions evaluated using the attributes of brilliance, fire, and scintillation. While high grades of color or clarity affect a diamond, it's the cut that determines its overall proportions and its ability to reflect light.

Diamond Cut Grade

The Cut Grade of a diamond directly impacts its beauty; if a diamond is designed, cut, and finished properly, it will have a much more desirable appearance, even when compared to diamonds of higher color and clarity grades.

 

Super Ideal:
Super Ideal Cut diamonds are extremely rare, with only 5% of diamonds receiving this grade. These diamonds include those with the most ideal specifications for every aspect of their cut.

Ideal:
Ideal Cut diamonds have a superior level of craftsmanship, emitting the most brilliance and light. Consumers seeking premium cuts prefer Ideal Cut diamonds.

Excellent:
Cut to a high-quality polish and symmetry, Excellent Cut diamonds will reflect all light as brilliance and fire.

Very Good:
A Very Good Cut diamond reflects nearly all light that enters. Less expensive than an Excellent Cut, it still displays a good amount of brilliance and sparkle.

Good:
An economical choice for the diamond shopper on a limited budget, a Good Cut reflects most light that enters it, offering beauty at an attractive value.

Fair:
A diamond with a Fair cut grade generates a decent amount of brilliance and fire. We advise that you choose a diamond with at least a Good cut grade if possible.

Diamond Cut Chart

The quality, depth and portions of a diamond’s cut determine it’s brilliance and sparkle. An expertly-cut diamond will achieve high levels of fire and scintillation.

Shallow-Cut Diamonds

A shallow cut diamond allows light to escape from its sides instead of reflecting off its top.

Shallow-Cut Diamonds

Ideal-Cut Diamonds

This premier cut style is well-proportioned and carefully angled to achieve a luminous appearance.

Ideal-Cut Diamonds

Deep-Cut Diamonds

A diamond whose cut is too deep will look smaller than diamonds of similar carat weight.

Deep-Cut Diamonds

Diamond Faceting

With modern diamond-cutting techniques, there are two common methods of cutting facets, each with its own unique, light-reflecting properties:

Step Cut Faceting

In this approach, the facets are elongated and placed in rows to simulate a mirrored staircase.

Brilliant Cut Faceting

This technique creates triangular-shaped facets that face outwards from the center of the diamond.

Step Cut Faceting

Light's Effect on a Diamond

There are many factors that affect a diamond’s brilliance, the most important of which is its ability to reflect light. As a diamond passes through a light source, tiny flashes will be visible within the stone.

Reflection

When light enters the surface of a diamond, a portion of it is reflected back out of the table (top).

Reflection

Refraction

The remaining rays of light travel into the center of the diamond and bounce off its internal walls.

Refraction

Dispersion

As light exits the diamond, dispersion causes the white light to be separated into multiple colors.

Dispersion

A Diamond's Depth

A diamond's depth can be determined by measuring the entire stone's height from the table to the culet and is described in millimeters. The depth percentage measures the ratio of a diamonds depth (from the table to the culet) to a diamonds total diameter. To learn about the ideal depth percentage for each diamond shape, visit our Diamond Shape page.

A Diamond's Depth | Brilliance.com

Polish & Symmetry

Diamond polish and symmetry are critical components to cut quality. For maximum brilliance, every facet of a diamond should be polished after the cutting process. A symmetrical diamond will have well-balanced and properly aligned facets. If the facets are not symmetrical or not optimally shaped, they'll display less sparkle.

Polish & Symmetry | Brilliance.com

Parts of a Diamond

A diamond is comprised of five main parts that affect its shape and radiance. Knowing these terms will help you understand the important components to consider when selecting a diamond. See also our Diamond Buying Guide Chart.

Table & Table Percentage

A diamond's table is the largest facet of the stone, comprising the flat surface on the top. The table percentage is the ratio of the width of the diamond's top facet in relation to the width of the entire stone. The right ratio results in a large amount of fire and brilliance. To learn about the ideal table percentage for each diamond shape, visit our Diamond Shape page.

Learn more about Diamond Table 

Table & Table Percentage

Crown

This is the top portion of the diamond, located above the girdle and extending below the table.

A diamond's crown extends from the top of the stone (the 'table') down to the girdle (the widest point of the diamond). Crowns can be comprised of step cut facets or brilliant cut facets.

Crown

Girdle

Forming the outer edge of the diamond, this is where the crown and the pavilion meet and is the widest part of a diamond.

This is the portion of the diamond between the crown and the pavilion, essentially spanning the width of the stone from side to side. The measurement of the girdle represents the perimeter of the diamond. A diamond's girdle can be rough, polished, or faceted, and does not typically affect the quality or appearance of the stone.

Learn more about Diamond Girdle 

Girdle

Pavilion

Located at the bottom of the diamond, the pavilion bridges the girdle and the culet and form at the bottom (culet).

Located between the girdle and the culet (point), the pavilion is integral to the stone's light reflecting properties. A properly cut pavilion will allow the maximum amount of light to reflect from the surface of the stone. An excessively deep or shallow diamond can cause light to escape out of the bottom and sides, reducing its sparkle.

Pavilion

Culet

The smallest facet of a diamond, the culet is located at the very bottom of the stone.

The smallest facet of a diamond, the culet is located at the very bottom of the stone. If the diamond ends in a point, the diamond grading report will show a value of 'None' for the culet designation. This small facet was originally intended to protect the diamond's pavilion, although today's settings are usually strong enough to render it unnecessary.

Learn more about Diamond Culet 

Culet
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