What Is Diamond Symmetry?

Symmetry, or the balance of equal parts, is what makes many things look pleasant to our eyes, from human faces to architecture and design. Symmetry is also crucial to understanding what a makes a diamond’s appearance so beautiful. Finished diamonds are graded on their symmetry, which is an important factor to keep in mind when you’re searching for an engagement ring. We’d like to explain more about what symmetry is and how it can affect the value of a diamond.

Diamond Education, Image of Diamond Symmetry

What is Symmetry?

In the diamond industry, symmetry refers to the exactitude of a diamond’s finished shape and the placement of its facets. Symmetry is one of the final parts of the detailing stage, or what is known as its “finish.” Together with a diamond’s polish, symmetry reveals the level of care taken during the cutting process.

How Is Symmetry Graded?

Symmetry is another criterion that the Gemological Institute of America (GIA) uses to judge the quality of a finished diamond.

Each stone is examined to make sure that all of the sides and facets are equal. A round brilliant diamond with good symmetry will have equal angles throughout the crown (the top half) and throughout the pavilion (the bottom half). It will also have facets of equal size and shape that meet at precise points, along with a number of other grading factors. GIA ratings range on a scale: Excellent, Very Good, Good, Fair, or Poor.

Is There A Difference Between Symmetry, Polish, and Cut?

The GIA uses the same rating terms (from Excellent to Poor) for polish, symmetry, and cut when grading standard round brilliant diamonds. But these criteria do not carry equal weight when determining the overall quality of a diamond.

A symmetry grade accounts for the arrangement and conformity of facets of a finished diamond, while a polish grade establishes the surface condition of a finished diamond’s facets. Both symmetry and polish grades are included in GIA reports for Kwiat diamonds.

Cut grades, however, rate the proportions and angles of a diamond. Cut has the most effect on a diamond’s ability to reflect and refract light. It is one of the 4Cs (along with color, clarity, and carat weight) known as the main standards for measuring a diamond’s worth.

While the GIA’s polish and symmetry grades are important, they are not equivalent to the grade of the cut, which is the most important of these three factors.


Our Symmetry Grades

Kwiat Tiara diamonds always receive the GIA’s Excellent grade for symmetry, along with the Excellent grade for polish and the Excellent grade for cut. Achieving Excellent grades in all three of these aspects is called “Triple Excellent” in the diamond industry and we are proud that Kwiat Tiara diamonds attain this level of distinction.

Why Symmetry Matters More For Round Diamonds

It’s important to note that the GIA does not grade cut for fancy shape diamonds, which represent all of the many non-round shapes. This is because fancy shapes follow less-specific guidelines for their cut. In general, a higher symmetry grade is more important when purchasing a round brilliant diamond because the cut is prescribed and finite.

Because symmetry is harder to assess in fancy shapes, it is rare to find one with a GIA Excellent rating. Symmetry grades for fancy shapes are quite nuanced, and nearly all variations between Excellent, Very Good, and Good are invisible without the aid of 10x magnification. Symmetry grades have less impact on the overall quality of fancy shapes as well. For fancy shapes, Kwiat diamonds have a symmetry grade between Excellent and Good.