The “C” for Diamond Color Measures The Whiteness Of A Diamond
Diamond color actually measures the diamond’s lack of color. The diamond color scale starts at D (colorless) through Z (the most color, typically a light yellow, brown, or gray color). The closer a diamond is to colorless, the higher the value, with the exception of fancy color diamonds; yellows, pinks, blues, etc. which have their own color range.
Most diamonds you’ll see in jewelry stores range from colorless to near-colorless, usually with a tint of yellow or brown.