Diamond Carat Weight

diamonds are weighed by a unit known as carat and a single carat corresponds to approximately 200 milligrams. The carat weight concept is based on the variation of specific gravity of precious stones. For instance, when two other precious stones such as ruby and emerald with the similar carat weights of a diamond are compared it would be found that the ruby is smaller in size and the emerald larger than the diamond. This is because the specific gravity of the ruby is more and that of the emerald is less than that of the diamond.

The name carat traces its origin to the seed of a tree found mainly in the Middle East. The weight uniformity of the dried seeds of this tree was favored by the ancient merchants of precious stones to use them as the standard for weighing these stones especially diamonds. The Greek name of this tree is keration and it is presumed that the name carat evolved from it. In the modern era when scientific principles were used to standardize diamond weighing the name carat was adopted to retain the aura of age old tradition.

Diamond weight is directly proportional to the quality of the stone and small shifts in quality and weight can make tremendous differences in value. A heavier diamond would be far more expensive per carat and the total cost of the stone would be much higher than the combined price of smaller diamonds that together correspond to its weight. The weight of a diamond has gradually replaced size as the most important factor that determines its market price.