The second of the 4Cs, a diamond's color is graded from D-Z with D being colorless, and the most desirable, and Z being a yellow or “cognac” color.

The only other diamond color more valuable than D are “fancy color” diamonds, which range from pink to blue (like the Hope Diamond) and are very rare.

Color grade is determined by comparing the diamond to an established set of diamonds with known color provided by the Gemological Institute of America. Here is the spectrum of diamond color grades:

D grade diamonds are very rare, but any diamonds with a grade D-F are considered colorless. G-I grade diamonds are near colorless, while J-M grades have a faint yellow hue. N-Z grade diamonds are considered yellow diamonds although the color varies in intensity from very light to a yellow-brown or “cognac” color.

The closer to D a diamond is on the color spectrum the more valuable it is, provided the other 4Cs are equal.

Go to Next Page: The 4 Cs: Clarity