Yellow diamonds are divided into two categories. Diamonds with a faint yellow tint are graded on the traditional D-Z color scale, where Z represents the strongest yellow within the colorless range. Beyond Z, the diamond is classified as a Fancy Color Diamond, where color becomes the defining characteristic.

Yellow diamonds make up the largest share of natural fancy color diamonds, yet only a limited number reach the intensity required for a Fancy grade.

Their color is created naturally by nitrogen within the diamond’s crystal structure. As blue light is absorbed, the diamond appears yellow. The stronger the effect, the more intense the color.

GIA grades fancy yellow diamonds by intensity: Fancy Light, Fancy, Fancy Intense, Fancy Vivid, Fancy Deep and Fancy Dark. The most desirable stones combine a pure, concentrated color with strong clarity and balanced proportions.

Botswana and South Africa are among the world’s important sources of natural yellow diamonds.