Color
The diamond color grade measures how colorless a diamond is.This scale refers only to colorless (white) diamonds, and not fancy colored gems like to yellow, and more rarely blue, green, orange and red.The color scale goes from D to Z (no diamond of color A, B or C has ever been found), with D being the most white and Z being the most yellow.
The most valuable diamonds are colorless.Colorless diamonds allow most light to pass through the stone and create the most brilliance.However, the majority of diamonds fall within a color range that runs from colorless (limpid) to near colorless and then to light yellowish or brownish.