Diamond colors grading scales

Diamond color grading scales[2] GIA Status: current AGS Status: current AGS Status: historical: pre 1995 CIBJO Status: current IDC Status: current Scan. D.N. Status: current Old World Terms Status: historical
grade and description[3] grade and electronic colorimeter scale[4] grade and electronic colorimeter scale[4] grade[5] grade and description[5] grade for .50ct and over[6] grade for under .50ct series 1 scale[5] series 2 scale[5]
D Colorless 0 0 - 0.49 0 0 - 0.75 Exceptional white + Exceptional white + Colorless River White Finest White Jager
E 0.5 0.5 - 0.99 Exceptional white Exceptional white River
1 0.76 - 1.35
F 1.0 1.0 - 1.49 Rare white + Rare white + Colorless when viewed through the crown Top Wesselton Fine White
2 1.36 - 2.00
G Near Colorless 1.5 1.5 - 1.99 Rare white Rare white Top Wesselton
H 2.0 2.0 - 2.49 3 2.01 - 2.50 White White Wesselton White Wesselton
I 2.5 2.5 - 2.99 4 2.51 - 3.0 Slightly tinted white Slightly tinted white Slightly colored Top Crystal Slightly tinted white Commercial White Top Crystal
J 3.0 3.0 - 3.49 5 3.01 - 3.75 Crystal Top silver cape Crystal
K Faint Yellow 3.5 3.5 - 3.99 Tinted white Tinted white Top cape Tinted white Top cape
6 3.76 - 4.5 Silver cape
L 4.0 4.0 - 4.49
M 4.5 4.5 - 4.99 7 4.51 - 5.50 Tinted color 1 Tinted color Slightly colored to colored Cape Tinted color Light cape Cape
N Very Light Yellow 5.0 5.0 - 5.49 Tinted color 2 Low Cape
O 5.5 5.5 - 5.99 8 5.51 - 7.0 Light yellow Cape Very light yellow
P 6.0 6.0 - 6.49 Light yellow
Q 6.5 6.5 - 6.99
R 7.0 7.0 - 7.49 9 7.01 - 8.5
Dark cape
S Light Yellow 7.5 7.5 - 7.99 Tinted color 3 Yellow
T 8.0 8.0 - 8.49
U 8.5 8.5 - 8.99 10 8.51 - 10.00
V 9.0 9.0 - 9.49
W 9.5 9.5 - 9.99
X 10.0 10 + 10+
Y
Z

"D" color has a unique "icy" look to it. Diamonds that rate toward the colorless end of the range are sometimes known as "high-color" diamonds, and those toward the other end, "low-color" diamonds. These terms refer to the relative desirability (as demonstrated by market prices) of color grades, not the intensity of the color itself.

[edit] Grading fancy color diamonds

Yellow or brown color diamonds having color more intense than "Z", as well as diamonds exhibiting color other than yellow or brown are considered fancy colored diamonds. These diamonds are graded using separate systems which indicate the characteristics of the color, and not just its presence. These color grading systems are more similar to those used for other colored gemstones, such as ruby, sapphire, or emerald, than they are to the system used for white diamonds.