About Diamond Weights

Diamonds are measured in Carat Weight. One carat weighs 200 milligrams. If a diamond is referred to as four grains, this also means that it is a one carat diamond.  The word Carat comes from the word carob. A carob is a bean that grows on a tree in the Mediterranean. In times past, if a diamond weighed the same as a carob bean, it was one carob, or one carat.

However, in the far east, where Carob trees do not grow, rice was used to measure the weight of a diamond. If a diamond weighed as much as four grains of rice, it was four grains – or one carat as we know it to be  now. The majority of diamond purchases are for diamonds that are 1/3 of a carat.
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