Color or lack of color is another attribute of a diamond. GIA grades on a color scale from D (colorless) to Z as the color increases. We select stones usually in a range of D-H for our clients. Occasionally, we will select something lower if it will be set in a yellow gold setting. Keep in mind the setting color will impact the color of a stone. We also ease up on our color requirements when we are purchasing a beautiful antique stone but we may choose to set the antique stone in yellow gold.