A guide to diamond certification

IGI certified.
Clarity in
every detail.

Beauty catches your eye. Understanding the details helps you choose. Discover what an IGI grading report can tell you about a diamond.

Verify your report Explore the details
A round brilliant diamond held in jeweller’s tweezers for a close inspection
The beauty you see. The details you can understand.

01 Independent grading

02 Diamond identification

03 Online report lookup

Beyond the sparkle

A closer look at
your diamond.

The International Gemological Institute (IGI) is an independent gemological laboratory. Its diamond reports bring the stone’s identifying details and grading results together in one place.

  1. 01

    Identity & origin

    The description identifies natural or laboratory-grown origin, alongside shape, cutting style and measurements.

  2. 02

    Grading & finish

    Look for the 4Cs, as applicable, together with details such as polish, symmetry and fluorescence.

  3. 03

    The finer details

    Review comments and any recorded laser inscription. Report formats and the information included can vary.

Natural diamond reports Lab-grown diamond reports
IGI sample natural diamond report showing identity, measurements, grading results and additional grading information
Sample report from IGI, shown for reference.
The report for your selected diamond will have its own details.

Understanding the 4Cs

Four details.
One individual diamond.

Read these characteristics together to understand a diamond beyond its appearance.

Cut

The way light moves

Proportions and craftsmanship influence how a diamond returns light, creating its brightness, fire and sparkle.

Color

The subtle differences

For diamonds in the D–Z range, color grading describes the degree of color present under controlled viewing conditions.

Clarity

A closer look within

Clarity describes internal and surface characteristics, assessed under 10× magnification.

Carat

A measure of weight

Carat measures a diamond’s weight. Two diamonds of the same weight can look different in size because of their proportions.

Learn more with IGI

Your report, at your fingertips

A little detail.
A simple check.

Have an IGI report? Look up its digital record directly with the institute.

Verify on IGI Opens the official IGI website in a new tab.
  1. 01

    Find your number

    Locate the IGI report number on your grading report.

  2. 02

    Open IGI’s report lookup

    Enter that number on the official IGI verification website.

  3. 03

    Review the details

    Compare the online record with your report, including the description, measurements and grades.

Good to know

Your questions,
made clear.

Talk to our team
What does “IGI certified” mean?

It commonly refers to a diamond accompanied by a grading report from the International Gemological Institute. The report documents the characteristics of the particular diamond examined.

Does IGI grade natural and lab-grown diamonds?

Yes. IGI grades both natural and laboratory-grown diamonds using the 4Cs. The report identifies the diamond’s origin so you can understand which type you are considering.

Is a grading report the same as an appraisal?

A grading report records a diamond’s identity and quality characteristics. An appraisal is a separate assessment of monetary value.

How do I find the report for a piece I like?

Contact our team with the product name or a photo. Ask about the report available for that particular piece and review its details before choosing.

Diamond Concepts

Let’s find your diamond.

Have a piece in mind? Bring your questions. We’re here to help you explore the details.

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