D-Z Color Grading Scale at Color

D-Z Color Grading Scale. Gia's diamond color grading scale is the industry’s most widely accepted grading system. D represents the most colorless and it goes down from there.

GIA 4Cs Color DtoZ
GIA 4Cs Color DtoZ from www.gia.edu

Each letter in the scale denotes a combination of tone. The scale begins with the letter d, representing colorless, and continues with increasing presence of color to the letter z, or light yellow or brown. Each letter grade has a clearly defined range of color appearance.

GIA 4Cs Color DtoZ

The 23 color grades on the gia color scale (or diamond color chart) are subdivided into five subcategories, which are: Gia's diamond color grading scale is the industry’s most widely accepted grading system. During grading color relates to how little color is present in a diamond or how white it is. The scale begins with the letter d, representing colorless, and continues, with increasing presence of color, to the letter z.