Diamond Color Grading System
In a effort to eliminate confusion related to diamond color, the Gemological Institute of America (GIA) implemented the color grading system in the 1950s which is still being used industry wide today. Diamonds are graded on a scale beginning with the letter D (colorless) and ending with Z (light yellow or brown). When creating the new color scale GIA chose to start with the letter D as a means of starting over. Prior to GIA implementing the D-Z scale, other systems all of which were inconsistent and inaccurate, already used the letters A-C, numbers 0-3, and the Roman numerals I-III.
It is important to note that diamonds at the end of the color range with a noticeable yellow tinge are not considered fancy yellow color diamonds.
Diamond Color Designations
D, E, F - colorless (white)
G, H, I, J - near colorless
K, L, M - faint yellow or brown
N, O, P, Q, R - very light yellow or brown
S, T, U, V, W, X, Y, Z - light yellow or brown
Diamond Color
D 100% Colorless. The highest color grade a diamond can receive. D graded diamonds are extremely rare and very highly priced.
E,F Colorless. Exceptionally transparent. Extremely difficult to detect the traces of color in an E or F graded diamond. These diamonds are rare and highly priced.
G,H Nearly Colorless. Unless these diamonds are compared next to a master stone of higher color grade, color is nearly indiscernable. Appear completely colorless when face up. These diamonds are still rare, but slightly less expensive and are considered a good value.
I,J Nearly Colorless. Color in these diamonds is slightly detectable. The slight amount of color is imperceptible by the unaided eye once the diamond has been mounted. Superior value.
K-M Faint Yellow. Noticeable color, although some diamonds in this range can still be fiery and beautiful.
N-Z Very Light or Light Yellow. Noticeable color. These diamonds are not fit to be sold as gemstones.
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