As with all precious gems, the weight of a diamond is expressed in carats. The carat originated as a natural unit of weight: the seed of the carob tree. Diamonds were traditionally weighed against these seeds. The system was later standardized and now one carat is divided into 100 points. This means that a diamond of 75 points weighs .75 carats or 3/4 carat.

Two diamonds of equal weight can have very unequal value, depending on their cut, color and clarity. Fine quality can be found in diamonds of all shapes and sizes, and, the larger a diamond is, the rarer and therefore more valuable.

Thus, a two-carat diamond will be more than double the price of a one-carat diamond of the same quality.