The Gemological Institute of America (GIA) is headquartered in Carslbad, California. Besides being a leading educational institute, the GIA provides diamond grading reports issued by the GIA Gem Trade Laboratory.
The GIA was established in 1931. GIA grades diamonds of all shapes and sizes and was the creator of the 4C's (clarity, colour, cut and carat weight).
A GIA Diamond Report is issued for diamonds of all shapes and sizes above 1.00ct. The report includes a comprehensive analysis of a diamonds quality and assessment of the diamonds 4C's – clarity, colour, cut and carat weight with a plot of the diamonds clarity characteristics. The report includes a Polish and Symmetry grade.
Example of GIA Grading Report
The GIA Diamond Dossier is a compact report for diamonds of all shapes weighing under 1.00ct on the GIA's D-Z colour scale. The Dossier includes analysis of the diamonds 4C's but does not include a plot of the diamonds clarity characteristics. All diamonds with a GIA Diamond Dossier's are laser inscribed on the girdle with the Dossier number.
Example of GIA Diamond Dossier