Diamond weight is determined in carats (many people think 'carat' refers to quality, which is incorrect).
The word "carat" comes from the "carob" seed, the original unit of measure for diamond traders. A carat is subdivided into a 100 points, therefore 50 points is half a carat.
A carat is equal to exactly 0.2 grams (about the weight of a paper clip). Carat weight is unrelated to the similar sounding karat, which refers to gold's purity.





