Colored Stone Report

The IGI Colored Stone Report identifies a natural colored gemstone’s species and variety. A detailed photograph is included, and the country of origin will be stated if gemological analysis conclusively reveals it.

Commitment to Confidence

IGI screens every diamond using state of the art technologies to determine naturally mined, laboratory grown or simulant origin. Experienced graduate gemologists conduct further assessment in controlled conditions, detailing relevant gemological characteristics according to the strictest international system. The presence of any permanent treatments will be noted in the comments section. IGI will not issue full grading reports for diamonds with non-permanent treatments.
Gemstones should only change hands when accompanied by a grading report attesting to quality. Regardless of location or marketplace, an authentic IGI Laboratory Report is the common language of trust and confidence in the gemological world.

How to read an IGI Natural Diamond Report

The IGI Natural Diamond Report includes the gemstone’s description, as well as its shape, cutting style, measurements and 4Cs assessments: Carat Weight, Color, Clarity and Cut.

Diamond reports may also include a graphic representation of the diamond’s proportions, a diagram of its clarity characteristics and a comment about its laser inscription, if one is present.

Grading Scale
D – F
G – J
Near Colorless
K – M
Slightly Tinted
N – P
Very Light Color
S – Z
Light Color

Internally Flawless
Very Very Slightly Included
VS 1-2
Very Slightly Included
Slightly Included

Learn More

For round brilliant diamonds, the overall proportions are compared with IGI studies of brightness, fire, scintillation and pattern to determine the Cut Grade. Fancy shaped diamonds are assessed using a four-step system combining finish assessment with proportions qualifications, shape-specific requirements and light return grading. All diamond shapes and colors will have craftsmanship grades for polish and symmetry noted on the grading report.

Cut Grading

Diamond color is graded in a standardized viewing environment. IGI gemologists analyze color in the D to Z color range with the diamond placed upside down, viewed through the side, to facilitate a neutral view. Multiple graders submit opinions independently, with no collaboration, and the grade is determined when there are sufficient agreeing opinions. Diamond clarity is assessed at 10X magnification. Grading depends on the visibility, size, number, location and nature of internal and surface characteristics at that magnification. Diamonds with characteristics which are immediately obvious or noticeable are likely candidates for lower grades, whereas diamonds with characteristics which are minor, minute or extremely difficult to see at that magnification may qualify for the higher grades.

IGI co-created the modern laser inscription process. Using a very fine and precise laser beam, alphanumeric characters, a brand logo or even a personalized message can be inscribed on the girdle or outside circumference of a diamond. Adding the report number to a diamond’s girdle with Laserscribe permits fast identification of a gemstone under magnification, verifying of all of its gemological details. Now standardized as an efficient and easy way to identify a diamond, the majority of diamonds around the world have laser inscriptions.


Warning: Undefined array key “r” in /home/customer/www/ on line 16

Verify Your Diamond

See a digital copy of your IGI grading report

Learn With Videos

A collection of two-minute videos designed to help shoppers make informed decisions when buying or selling diamonds, gems, and jewelry.

All Videos

Lab Grown Diamonds

Did you know? Only natural and lab grown diamonds score 10 on the Mohs hardness scale; nothing else comes close.

Learn More

Carat Weight

Did you know? Diamonds of the same carat weight do not necessarily appear to be the same size.


Did you know? Gemologists perform D to Z color grading with the diamond upside down, viewed through the side.

Learn More

Related Reports

Regardless of location or marketplace, an authentic IGI Laboratory Report is the common language of trust and confidence in the gemological world.

All Reports

Natural Diamond Report

IGI Natural Diamond Reports give an accurate assessment of a diamond’s cut, color, clarity and carat weight according to strict international standards.

Natural Diamond Report

Lab Grown Diamonds

See how laboratory grown diamonds are physically, optically and chemically identical to natural diamonds which formed in the earth.

Lab Grown Diamonds