How to Read Your Diamond Certificate

June 14, 2019 By swj-eric

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A Diamond Certificate is the official grading report of a diamond. This document lists the stone’s most important details, including the diamond’s cut and color grade.

However, if you’re new to the sparkling world of diamonds, you might wonder what all this information means.

Take the time to learn how to read your diamond certificate. By understanding each section, you’ll feel more confident when it’s time to Sell Your Diamond.

1. Laboratory Name

At the top of the report, you’ll find the name of the laboratory that supplied the certificate.

This is also one of the most important details. While there are many labs that can issue diamond certificates, the Gemological Institute of America (GIA) and the American Gem Society (AGS) are the most trusted sources.

The GIA and AGS have strict grading guidelines. Consequently, you can be sure that the information on the certificate is specific, accurate, and held to high standards. Lesser-known labs often have relaxed guidelines, making it easy to over-grade diamonds of poor quality.

2. Report Number

The report number is a set of digits assigned to your certificate. It allows the lab to record your report, much like your phone provider uses statement numbers your bills.

With this number, a person can look up and verify the certificate on the lab’s website. For example, if you’re Selling Your Diamond and have a potential buyer, they could use this report number to confirm the document’s authenticity.

Plus, if you need to replace a lost certificate, the lab can use this report number to search their records and produce a new one.

3. Laser Inscription Number

If you have a certified diamond that’s been laser etched with an ID number, the number will be on the report. For diamonds that have been graded by the GIA, the laser inscription is the same as the report number.

Often, the inscription is etched on the diamond’s girdle, or the perimeter of the widest part of the stone.

This number helps potential buyers ensure that the diamond belongs to the certificate provided.

4. Shape and Cutting Style

Under the report number you’ll find “shape and cutting style.”

While many people use “shape” and “cut” interchangeably, the terms mean different things.

The shape is the figure of the diamond, such as:

  • round
  • square
  • rectangle
  • heart
  • oval
  • pear
  • triangle

The cut is the style of facets, or surfaces, of the gemstone. Examples of cuts include:

  • brilliant cut
  • modified brilliant cut (princess, marquise, oval, etc.)
  • step cut
  • single cut

The shape and cut are listed together. For example, it might read “square brilliant” or “round modified brilliant.”

5. Measurements

Next is the diamond’s measurements, or the stone’s physical dimensions, in millimeters.

A trained eye will be able to determine if the diamond has ideal proportions by comparing the measurements to the shape and cutting styles.

6. The Four C’s

Under “grading results,” the famous “four c’s” will be listed. This includes:

Carat Weight

This number is the diamond’s weight measured in carats.

Color Grade

The color grade is a letter that indicates the diamond’s color. These letter grades include:

  • Colorless, pure white diamonds: D, E, or F
  • Off-white diamonds: G or H
  • Faint yellow diamonds: K, L, or M
  • Very light yellow diamonds: N, O, P, Q, or R.
  • Light yellow: S through Z
  • Fancy color diamonds: Z+

Clarity Grade

According to the GIA, the clarity grade is the “absence of inclusions and blemishes.”

After all, diamonds are created by nature, so it’s likely that they’ll have inclusions and blemishes.

The clarity levels include:

  • FL: Flawless
  • IF: Internally Flawless
  • VVS1 and VVS2: Very, Very Slightly Included
  • VS1 and VS2: Very Slightly Included
  • SI1 and SI2: Slightly Included
  • I1, I2, and I3: Included

Cut Grade

On certificates issued after 2006, you’ll find a Cut Grade. This refers to how well the diamond reflects light and sparkles.

The cut grade isn’t assigned by how beautiful it looks, though. At the GIA, a gemologist will calculate the proportions and measurements of the diamond’s surfaces. These calculations will indicate how the stone interacts with light.

Cut grades include:

  • Excellent
  • Very good
  • Good
  • Fair
  • Poor

7. Additional Grading Information

Here, you’ll find polish and symmetry, which uses the same grades as cut grades. (Excellent, very good, etc.)

Polish refers to the smoothness of the stone’s surface. Symmetry compares how its faces align with each other.

Fluorescence indicates whether a diamond glows under UV light. Most people prefer diamonds without fluorescence, as this can sometimes make the stone look cloudy. If a diamond doesn’t have fluorescence, the certificate will list “none.”

The inscription and other comments will also be listed in this section.

Have questions? Southwest Jewelry Buyers can explain your diamond certificate.

If you’re new to selling gemstones, learning how to read a diamond certificate is crucial. It allows you to fully understand your diamond’s features, and therefore, get a fair price.

We’re also happy to look at your diamond certificate and break down the information. Besides, our jewelry buyers are GIA-certified, so you can be sure that they know how to read a GIA certificate!

When you’re ready to Sell Your Diamond In Arizona, we’ll offer top dollar on the spot. From there, you can expect a professional and comfortable transaction with our team of ethical jewelry buyers.

To schedule an appointment, Contact Southwest Jewelry Buyers at (480) 773-8004.