The Fourth "C": CARAT

What Diamond “Carat Weight” Means and How Diamonds Are Sold By Their Weight

Diamonds are identified and sold by their carat weight, which is not the same as karat, which refers to the purity of gold, as in 14 karat, 18 karat, etc. When talking about diamonds, 1 carat equals 100 points. (Helpful Tip: To clarify the concept of 100 points equaling 1 carat, think of 100 pennies equaling 1 dollar.)

Many people, including jewelers, refer to diamonds as a percentage of their overall carat weight, as in a “quarter carat,” a “half carat,” or “a three-quarter carat” stone. This is a handy shorthand for describing the general range of a diamond’s size, but you should know that a “quarter carat” diamond does not always refer to a diamond that weighs precisely 25 points.

This chart will illustrate the range of diamond weights used in the jewelry industry. Be aware, however, that no matter how a ring or a diamond is described (“this wedding band has a third of a carat total weight of diamonds”) you should always be told the precise weight -- in points -- of the diamond or diamonds you are purchasing.


DIAMOND CARAT WEIGHT = DIAMOND WEIGHT RANGE

Melees 0.001 - 0.04 Ct.
1/20 Carat 0.05 - 0.09 Ct.
1/10 Carat 0.10 - 0.16 Ct.
1/6 Carat 0.17 - 0.19 Ct.
1/5 Carat 0.20 - 0.24 Ct.
1/4 Carat 0.25 - 0.32 Ct.
1/3 Carat 0.33 - 0.37 Ct.
3/8 Carat 0.38 - 0.49 Ct.
1/2 Carat 0.50 - 0.74 Ct.
3/4 Carat 0.75 - 0.87 Ct.
7/8 Carat 0.88 - 0.99 Ct.
Full Carat 1 Carat (100 points)