---
title: "Color grade: meaning in gemology"
description: "The color grade is a letter from D to Z for the yellow or brown tint of a near-colorless diamond. D is colorless and Z is light yellow or brown."
url: https://digitalgemology.com/learn/glossary/color-grade
image: https://digitalgemology.com/img/og-digital-gemology.png?v=d224fb01
---

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[Glossary](https://digitalgemology.com/learn/glossary) · Four Cs

# Color grade

Also called diamond color, D-to-Z scale, D to Z color scale, color

The color grade is a letter from D to Z for the yellow or brown tint of a near-colorless diamond. D is colorless and Z is light yellow or brown.

## In more detail

Its 23 letters fall into five ranges: colorless, near colorless, faint, very light and light. GIA started the scale at D to break with the vague A, B and C grades of the past. Labs grade color against master diamonds in standard light, because warm or dim light hides small steps. A diamond with more color than Z leaves the scale and can get a fancy color grade.

## On a grading report

In the grades block. An asterisk after the letter means a detected color treatment. IGI also grades D to Z and groups the letters into named bands.

## Related terms

- [Master stones](https://digitalgemology.com/learn/glossary/master-stones): Master stones are reference diamonds of known color grade. A grader sets a diamond beside them to decide its D-to-Z letter.
- [Colorless (D–F)](https://digitalgemology.com/learn/glossary/colorless): Colorless is the top range of the D-to-Z scale: the grades D, E and F.
- [Near colorless (G–J)](https://digitalgemology.com/learn/glossary/near-colorless): Near colorless is the D-to-Z range from G to J.
- [Fancy color diamond](https://digitalgemology.com/learn/glossary/fancy-color-diamond): A fancy color diamond is a colored diamond with enough color for a fancy grade. To GIA, any diamond outside the D-to-Z scale is a colored diamond.
- [Asterisk after the color grade](https://digitalgemology.com/learn/glossary/asterisk-color-grade): An asterisk (*) after a GIA color grade means that the lab detected a color treatment. Comments explains what it is.
- [Fluorescence](https://digitalgemology.com/learn/glossary/fluorescence): Fluorescence is visible light, almost always blue, that some diamonds give off while ultraviolet light shines on them. It stops when the UV goes off.

## Learn more

- [The diamond color scale, D to Z: where you first see a tint](https://digitalgemology.com/learn/four-cs/diamond-color-scale-d-to-z)
- [The grades on a diamond report: color, clarity and cut](https://digitalgemology.com/learn/grading-reports/diamond-report-grades)
- [Moissanite color and fluorescence compared with diamond](https://digitalgemology.com/learn/diamond-vs-moissanite/moissanite-color-and-fluorescence)

[All 328 terms](https://digitalgemology.com/learn/glossary)