Grading fancy color diamonds
Yellow or brown colored diamonds having a color grade more intense than "Z", as well as diamonds exhibiting color other than yellow or brown, such as blue or pink are also considered fancy colored diamonds.
Colored diamond grading system
GIA and EGL-USA issues a Colored Diamond Grading Report for colors that are not in the normal color range of diamonds.
The following are terms used to describe natural yellow diamonds:
Fancy Vivid Yellow - most unique diamonds and considered the rarest. Its very rich and vividly intense hue among all other ranges makes it the most expensive range of all fancy diamonds.
Fancy Intense Yellow - Richer color and quality. Value is higher compared to Fancy Yellow diamonds.
Fancy Yellow - a lesser saturated yellow hue compared to the Fancy Intense Yellow.
Light Fancy Yellow - a slight yellow tint that can be detected by human eye.