How to Read Your GIA Certificate

Your Diamond Grading Report is an objective description of all of the characteristics of your unique diamond, from the Gemological Institute of America, the world's most respected non-profit source of knowledge about gemstones. This report details your diamond's official measurements, color and clarity, and more, as well as an assurance that your diamond is a natural diamond.

The left part of your report identifies the date of the assessment, and a list of all of your diamond's properties. Each gemstone is issued its own unique number, which can also be inscribed on the diamond by laser.

Shape and Cutting Style

This describes the shape of the outline of the diamond and the pattern in which the facets have been arranged, or cutting style. The shape of a diamond describes the outline of its girdle, and includes: Round, Oval, Radiant, Asscher, Marquise, Princess, Emerald, Pear, Heart, and Cushion.

Measurements

Dimensions, in millimeters, of the diamond, rounded to the nearest hundredth.

Carat Weight

Diamond carat weight is the measurement of how much a diamond weighs. A metric "carat" is defined as 200 milligrams. A single carat = 0.2 grams

Color Grade

Colorless diamonds are typically labeled on a color scale from D to Z, with D being truly colorless and Z possessing clearly visible yellow or brown color.

Where the colorless scale ends, the world of fancy color diamonds begins. Using a controlled viewing and lighting environment and a comprehensive set of color comparators, the GIA grades fancy colors on a scale ranging from “Faint” and “Very Light”, to “Fancy Deep” and “Fancy Vivid”- vibrant color that surges through the stone.

Color Origin

The source of the diamond's color — purely natural, or a treated synthetic or natural diamond.

Color Distribution

This refers to how evenly color is distributed throughout the diamond when viewed face-up. The greater the distribution, the more evenly the color is distributed. Distribution is categorized as “Even” – symmetrical in over 50% of the stone, “Uneven” – asymmetrical in over 50% of the stone, or “Not Applicable” for the grades Faint, Very Light, and Light.

Clarity Grade

This is a description of the degree of inclusions or flaws in the diamond, The GIA rates clarity on a scale of Flawless – no inclusions or blemishes visible under 10x magnification, to Included – where inclusions are obvious under 10x magnification.

IF VVS1 - VVS2 VS1 - VS2 SI1 - SI2 I1-I2-I3
INTERNALLY
FLAWLESS
VERY,VERY SLIGHTLY
INCLUDED 1 AND 2
VERY SLIGHTLY INCLUDED
1 AND 2
SLIGHTLY INCLUDED
1 AND 2
INCLUDED
1, 2 AND 3

Proportions

The proportions of the diamond are presented graphically

Polish

This is a grade of how smooth the diamond surface is and if any marks remain from polishing the facets. It is graded on a scale of Excellent, Very Good, Good, Fair, Poor.

Symmetry

This refers to the exactness of the shape of a diamond, and thearrangement and even placement of the facets. Like Polish, Symmetry is also assessed on a scale ranging from Excellent to Poor.

Fluorescence

Fluorescence describes the degree of sensitivity of a diamond to long wave ultraviolet radiation.

The right section of the certificate contains diagrams to help you better understand the diamond's clarity and color characteristics.

GIA Colored Diamond Scale

This scale displays the general interrelation of GIA fancy color grade terms, used to describe the combined effect of tone and saturation.

Clarity Characteristics

This is a visual representation of any indications of inclusions or blemishes on your stone.

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