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Your Diamond Guide
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Whatarediamonds.com. All rights reserved. 2006
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What is GIA Grading?
In the 1950’s, the Gemological Institute of America
(GIA) developed the first international accepted
diamond grading system. This system provides
unbiased opinions of the quality of polished diamonds
by applying uniform criteria to their grading.
The Institute’s history of education research,
laboratory service, and instrument development
reads much like a chronicle of the jewelry industry’s
own growth and sophistication.
GIA is the creator of the famous 4Cs of diamond value
(color, clarity, cut and carat weight). Today, GIA’s D-Z
color grading scale and GIA’s Flawless-I3 clarity-
grading scale are recognized by virtually every
professional jeweler and developed and patented the
first modern jeweler’s loupe. The GIA Diamond
Grading Report and the GIA Diamond Dossier are
considered the world’s premier gemological
credentials. Diamonds of all shapes and sizes are
sent to the Institute from all around the world for
analysis and grading.
A completed certificate includes an analysis of the
diamond.
The shape and cutting style
The diamond dimensions in millimeters
The weight of the diamond to the nearest hundredth
of a carat
The depth and /or width relative to diameter
The table facet and/or width relative to diameter
The range of girdle thickness
The appearance of the cutlet facet
The clarity grade determined under 10x magnification
The map of the approximate size, type and position of
inclusions as viewed under a microscope
The grade of color
And a comment of any additional characteristic not
already mentioned in the report.
The New GIA Diamond Grading Report and GIA
Diamond Dossier
Since January1, 2006, the GIA lab issued an updated
version of the GIA Diamond Grading Report and GIA
Diamond Dossier. That is a new GIA Diamond Cut
Grading system. Research had showed that there is
no single set of proportions that define a well-cut
round brilliant diamond. In fact, many different
proportions can produce attractive diamonds. The
new grading system will provide a single,
comprehensive cut grade for all standard round
brilliant diamonds falling in the GIA D-Z color scale
and Flawless-I3 clarity scale. Diamonds will receive
one of five cut grades from Excellent to Poor.
New diagram will provide all the proportions used to
determine the GIA cut grade. The procedures
established by GIA also determined the nature of
each diamond. The Institute only grades natural
diamonds and it discloses any evidence of treatment
detected during the grading process on the diamond
grading report.
