Diamond Carat
Cut | Clarity | Colour | Carat
Carat Weight
The weight of a diamond is generally given in carats. The term carat originated in ancient times when gemstones were weighted against the carob bean. Each bean weighed about one carat. In 1913, carat weight was standardized internationally and adapted to the metric system. One carat equals 0.2 grams – So a 5ct stone will weigh 1 gram.
Carat and karat are often confused. Karat refers to the fineness of gold alloys (pure gold is 24 karat;18 karat is 18 parts gold and 6 parts other metals) and carat refers to gem weights.
The weight of small diamonds is frequently expressed in points, with one point equaling 0.01 carats. For example, five points is a short way of saying 5/100 of a carat and fifty points equates to a half carat. There are 100 point to a carat.
Sometimes in the jewellery trade, the term size is used as a synonym for carat weight. This is because small round diamonds having the same weight also look the same size and similar diameters. As diamonds increase in weight, their size becomes less predictable. Diamonds with a shallow cut can have a greater diameter than a deeper cut diamond with the same weight. However, you don't want the diamond to be too shallow or it will not reflect the light properly and will have less brilliance.