A Diamond Grading Report documents the specific characteristics of a diamond. These reports are issued by the Gemmological Institute of America (GIA), which is among the most respected organizations in the diamond industry.

GIA Diamond Grading Report

The GIA set the standard for diamond grading and gemmological identification, and their grading system serves as the international gem and jewellery industry's benchmark credentials.

Diamond Characteristics Documented in the Diamond Grading Report

    Shape and Cutting Style: The diamond shape and cutting style.

    Measurement: Lists the diamond's dimensions in millimeters.

    Carat Weight: The weight of diamond listed to the nearest hundredth of a carat.

    Colour Grade: A grading which assesses the absence of colour in a diamond.

    Clarity Grade: Clarity grade determined under 10x magnification.

    Cut Grade: A grade of cut as determined by a diamond's face-up appearance, design and craftsmanship. A cut grade is available on round diamonds graded after Jan. 1, 2006.

    Finish: Grades that represent a diamond's surface and facet placement.

    Polish: Rating the overall smoothness of the diamond's surface.

    Symmetry: Measuring the shape, alignment and placement of the diamond's facets in relation to one another as well as the evenness of the outline.

    Fluorescence: Colour, and strength of colour when diamond is viewed under UV light.

    Comments: A description of additional diamond characteristics not already mentioned in the report.

    Clarity Plot: A map of the approximate size, type, and position of inclusions as viewed under a microscope.

    Proportion Diagram: A map of the diamond's actual proportions.

Reading a Proportion Diagram

Proportion diagrams will typically include the following information:

    Depth: The height of a gemstone measured from the culet to the table.

    Table: Located at the top of the diamond, the table is the largest facet of a diamond.

    Girdle: Range of girdle thickness.

    Culet: Appearance, or lack thereof, of the culet facet.

 
For More Information
Learn about our appraisals and other grading reports that accompany diamonds from Blue Nile.

GIA Diamond Grading Report
GIA Diamond Dossier®
AGSL Diamond Quality Document
GCAL Diamond Certificate of Authenticity
Blue Nile Appraisal