The carat (cts.) is the standard unit of measurement used to indicate the weight of diamonds. One carat is equal to 200 milligrams or 0.2 grams. The larger diamonds are found far less often than smaller diamonds thus the price of a diamond increases exponentially as the carat size of the diamond increases.
The word carat is derived from ancient times, when gems were measured using the weight of a carob seed. One carat is equivalent to one fifth of a gram. It can also be divided into 100 points. If someone refers to a half carat diamond, this is the same as a 50 point or a 0.50 carat diamond.
Carat Size Chart:
The size or carat weight of a diamond cannot be used alone to determine the value of a diamond. A large diamond cannot be as valuable if it does not show good color, a fine cut or excellent clarity. All factors (4C’s: cut, color, clarity and carat) are used together to determine the right value of a diamond.