Diamond Grading: How Diamond Quality Is Determined

VRAI | March 24, 2022

Diamonds are graded according to the [4Cs]/journal/post/diamonds-defined-the-ultimate-4cs-guide) — cut, color, clarity, and carat weight. These grades determine the quality and value of a diamond. Once a diamond’s 4Cs have been assessed by a gemologist, they register this information in a diamond grading report.

Understanding how diamond quality is evaluated is important when purchasing your own diamond. Learn about the grading scale to find the VRAI created diamond that’s right for you.

What are diamond grading scales?

The GIA created an almost universally adopted set of standards referred to as grading scales or grading charts. These scales determine the quality of each of the 4Cs and directly influence a diamond’s value.

Cut Scale

Cut describes how a diamond’s surface interacts with and catches light. The quality of the cut is evaluated by factors such as a diamond’s brightness, fire, scintillation, polish, and symmetry. The cut is then graded from Excellent to Poor on the GIA scale.

VRAI’s cut scale also includes “Ideal”and “Ideal + Hearts” for Round Brilliant diamonds, which are levels above Excellent.

diamond cut
diamond cut

Color Scale

Color actually refers to the absence of color. The closer to colorless a white diamond is, the more valuable it becomes. Color is graded on a scale from D-Z (A, B, and C were used before GIA standards were set and are considered outdated). D- F diamonds are graded as colorless and G-J are near colorless.

diamond color scale
diamond color scale

Clarity Scale

Clarity refers to the visual purity of a diamond. It is determined by the number of inclusions and blemishes — marks that naturally occur during a diamond’s growth, often invisible to the naked eye. Clarity is graded from Flawless to Included.

Within the scale are very, very slightly included or VVS1 and VVS2 diamonds, Very slightly included, or VS1 and VS2 diamonds, and Slightly included, or SI1 and SI2 diamonds.

diamond clarity scale
diamond clarity scale

Carat

Carat is the most objective C to determine as it refers to a diamond’s weight. A carat is defined as 200 milligram and is divided into 100 “points.” These points mean that your diamond weight is measured to the hundredth decimal place.

A carat weight size indication scale estimates a diamond’s size based on its carat weight. But certain diamond shapes, like Oval or Marquise, appear larger than other shapes with the same carat weight.

What are the best diamond grades?

Each of the 4Cs has a “top” grade that certifies excellent quality and high value. However, certain grades matter more depending on a diamond’s shape, what kind of design it will be featured in, and other factors such as the metal color it will be set in. So balance the best diamond grades with your specific needs to find the diamond that’s right for you.

  • The best grade for diamond cut is “excellent” on the GIA scale. For Round Brilliant VRAI created diamonds, VRAI uses “Ideal + Hearts” for its best cut grade.
  • The best grade for diamond color is “D.”
  • The best grade for clarity is “flawless.”
  • There is no “best” grade for carat weight, but VRAI created diamonds up to 7 carats are available depending on the shape.

Diamond Grading Report vs Diamond Certificate

A diamond grading report is an assessment of a diamond’s quality based on the 4Cs. It is usually provided by a gemologist or a third-party laboratory such as GIA or IGI.

A diamond certificate records a diamond’s grade as well as other pertinent information, such as a diamond’s origin and the diamond warranty.

VRAI's diamond certificate provides the same information as a third-party laboratory report, but also offers the following: GIA Diamond Grading Scale GIA Gemologist grading report Gemologist Certification Certified Carbon Neutral® Stamp

How Are VRAI Created Diamonds Graded?

VRAI created diamonds are graded by a carefully selected group of in-house, GIA-trained and certified gemologists.

The decision to use in-house gemologists came after VRAI created diamonds were tested at leading grading laboratories and came back with varied results. This included the same diamonds receiving different results after being tested twice by different labs. The problem was human error; graders were not using tools more advanced than a microscope to help with their evaluations.

VRAI measures and stores more than one billion data points on each carat of diamond grown in our zero-emission foundry. This massive amount of data, however, was not being used by third-party graders. Our foundry also applies the most advanced optical metrology to each diamond, which provides the physical basis for their clarity and color.

Ultimately, it was determined that in-house-gemologists were better equipped to assess the quality of each VRAI created diamond. They can assess the quality and value of each VRAI created diamond with our foundry’s data and technical advantages for more accurate diamond grades.

VRAI provides certification for every engagement ring featuring diamonds 1/2ct and above and jewelry designs featuring diamonds 1ct and up. The certificate outlines and guarantees the details of that specific stone. Unlike other diamond reports, VRAI guarantees the grade of your diamond with a full producer warranty.

What are GIA certified diamonds?

A GIA certified diamond is a diamond that has gone through a meticulous grading process developed by the Gemologist Institute of America (GIA). The grading is most often done by GIA certified gemologists, who then record a diamond’s quality in a certificate or report.

Speak with our diamond experts

For in-depth diamond education and guidance in finding the VRAI created diamond meant for you, book an in-person or virtual appointment with our diamond experts. They will guide you through our diamond inventory and help you select a setting to highlight your diamond from zero-emission foundry.