The carat is the standard unit of weight, not size, of a gemstone. There are 100 points to a carat and one carat is equal to 200 milligrams. Therefore a 50 point diamond is 1/2 a carat, or 100 milligrams. Larger diamonds are found relatively infrequently in nature and are therefore more valuable. The cost of a diamond increases exponentially with its weight. So a 1-carat diamond will cost more than twice a 1/2-carat diamond, all other things considered. However, the cut and mounting can make a diamond appear much larger or smaller than it actually is.

The term carat is often confused with the term karat. Karat refers to the purity of the gold, not its weight.

[Before the 4 C's] [Color] [Clarity] [Cut] [Carat] [Care]