The GIA Diamond Color Scale
The Gemological Institute of America (GIA) color scale for white or colorless diamonds ranges from grades D to Z. Any stone within that range falls within the “normal color range.”
The most highly valued diamonds have no color. Thus, the more color a stone has (yellow or brown), the lower the grade. Yellow or brown diamonds that make it past the Z grade, however, instantly go up in price. Such diamonds have enough color to be considered “fancy,” along with pink, green, and blue diamonds. (Once these diamonds have enough saturation to show these colors, they are automatically considered fancy).
As with other diamond grading scales, diamond value goes up exponentially with each increase in grade. (Conversely, value goes down exponentially as the color grade decreases). Whereas diamonds of any carat size hold value and find use, diamonds between L and V color grades appear less often in jewelry.
The GIA D-Z scale is divided into five categories:
- Colorless — D, E, F.
- Near Colorless — G, H, I, J.
- Faint — K, L, M.
- Very Light — N, O, P, Q, R.
- Light — S, T, U, V, W, X, Y, Z.