Triple X diamond is a trade term referring to stones that have Excellent cut, polish and symmetry on their GIA grading reports. GIA does not use this term but many jewelers do. Does Triple X rating matter and should you pay more for a Triple X diamond?

In this blog we’ll cover:
What is a Triple X diamond?
What is Excellent cut?
What is Excellent symmetry?
What is Excellent polish?
Should I only buy Triple X diamonds?
Are Triple X diamonds rare?
Can I save money by not buying a Triple X diamond?

What is a Triple X diamond?

Triple X diamond is a trade term for round brilliant diamonds that have been graded by GIA as having Excellent cut, Excellent symmetry and Excellent polish. X is short for Excellent, so Triple X really just means Triple Excellent.

A diamond’s cut, symmetry and polish grades indicate the quality of craftsmanship that went into transforming a diamond rough into a polished stone. All three affect a diamond’s interaction with light and are described on GIA Diamond Grading Reports as Excellent, Very Good, Good, Fair, to Poor .

Many diamond buyers seek out Triple Excellent diamonds because they want diamonds with the best possible craftsmanship. Top notch craftsmanship ensures that a diamond gives off maximum light and fire while having an attractive pattern.

What is Excellent Cut?

This 0.73 ct diamond has Excellent cut, J color and VS1 clarity. An Excellent cut can help improve a diamond’s color. Photo: Kevin Schumacher/GIA.

Cut is a diamond’s most important factor. It determines a diamond’s proportions — its depth and the angles of its facets — which in turn affect how light bounces around in a diamond. An Excellent cut grade means that a diamond has been cut within parameters that allow the diamond to give off intense brightness, sparkle and fire, while having an even pattern of light and dark areas (scintillation). Poorly cut diamonds often have large light or dark patches that make the stone appear dull or uninteresting to the eye.

This trio of diamonds demonstrates why cut is important. These diamonds have cut grades — Excellent, Good, Poor — from left to right. Photo: Kevin Schumacher/GIA

What is Excellent symmetry?

This diagram shows the facets of a round brilliant diamond and how they should line up. Illustration: Peter Johnston/GIA.

Symmetry is about the exactness of a diamond’s shape. It refers to how well-aligned the facets are and how identical the same types of facets are in size, shape and proportion. In a diamond with Excellent symmetry, all of the facets should meet at the girdle (the widest part of the diamond). And the points of the kite-shaped facets on the crown (top of the diamond) should align with the points of the wedge-shaped facets on the pavilion (bottom of the diamond). The large octagonal table facet at the top should be centered, while the pavilion facets at the bottom should meet in a perfect point at the tip of the diamond. Excellent symmetry enhances a diamond’s light return and can make a diamond appear more harmonious to the eye.

What is Excellent polish?

Polish is the quality of a diamond’s finish or how smoothly the surface of a diamond has been polished. A diamond with Excellent polish has no polish defects visible at 10× magnification. Small surface defects, such as pits and polish lines, are often created by the polishing wheel during the polishing process and can usually be removed through re-polishing. While they are often invisible to the unaided eye, having a lot of surface defects will dim the shine and sparkle of the stone.

Think of the diamond’s facets as mirrors. The smoother the surface, the more perfect the reflection. The diamond gathers light through these mirrors (facets) from around the observer. When a diamond has the right proportions and symmetry, the mirrors reflect that light as a dazzling play of brightness, fire and scintillation.








Should I only buy Triple X diamonds?

A diamond doesn’t need to be Triple X to be of high quality. While symmetry and polish both influence a diamond’s overall cut grade, they don’t need to be rated Excellent for the diamond to receive an Excellent cut grade. Diamonds with Very Good symmetry or Very Good polish can still have an Excellent cut grade. That’s because the difference between a diamond with Excellent symmetry and polish and a diamond with Very Good symmetry and polish is only obvious under magnification.

In addition, a Triple X cut diamond can still look dull if it has eye-visible inclusions or extremely strong fluorescence. Cut, polish and symmetry grades need to be considered in relation to other quality factors.

Although not a Triple X diamond, this ring still looks beautiful. The 2.03 ct center diamond has Excellent cut, Very Good polish and Very Good symmetry. It is G color with VS2 clarity. Courtesy: 1stdibs.com

Are Triple X diamonds rare?

Due to technological advances and consumer demand, a Triple X rating diamond is easy to find. Diamond manufacturers routinely cut diamonds to the cut standards that GIA defined.

When GIA developed its cut grade for round brilliant diamonds in 2005, it conducted extensive research on the diamond scintillation patterns that people found attractive and documented the diamond proportions and cutting parameters used to create these patterns. These cutting parameters were then given to cutting centers which used them to cut diamonds. Since then, these proportions and parameters have become standard and widespread in the industry. Many companies have machines that automatically cut diamonds to the best proportions possible. Triple X diamonds have therefore become increasingly common.

A high-quality, well-crafted diamond is breathtaking. This 51.71 carat, round brilliant diamond has been graded by GIA as D Flawless with Excellent cut, polish and symmetry. Courtesy: Sotheby’s.

Can I save money by not buying a Triple X diamond?

Diamonds with an Excellent cut grade, Very Good polish, and Very Good symmetry cost less than Triple X diamonds, providing all else is the same. The visual difference between them and a Triple X diamond will rarely be obvious to the unaided eye. But buyers who truly wish to save money on a diamond should also consider choosing a diamond with a lower color, clarity or carat weight or consider getting a diamond with faint or medium fluorescence. These reductions may result in greater price decrease without necessarily reducing the visual impact of the diamond. Learn how to prioritize the 4Cs to save money on your diamond purchase.

At the end of the day, a diamond’s quality must be considered holistically with all factors taken into consideration. The Triple X designation is only meaningful if the diamond also has good color and clarity. Triple X diamonds cost a little more than diamonds with lower cut, polish and symmetry grades, but the price difference might be worth it to discerning buyers. After all, the Triple X designation signals that a diamond has been carefully and masterfully crafted.

Learn more about how GIA grades cut, polish and symmetry and how these are described on a GIA Diamond Grading Report.