One carat is equivalent to one fifth of a gram. It can also be divided into 100 ‘points.’ If someone refers to a half carat diamond, this is the same as a 50 point or a 0.50 carat diamond. Similarly, a quarter carat diamond is equivalent to 25 point, or 0.25 carat.
If a piece of jewelry contains more than one diamond, for example a diamond cluster ring or a diamond three stone pendant, the stated carat weight reflects the total weight of all the stones together, rather than each individual diamond.
The carat weight of a diamond does not reflect its size. One diamond may look bigger than another but weigh less. A good cut and certain mounts can make a diamond appear larger than its actual carat weight, so it’s worth taking your time to find the right setting that optimises its beauty and brilliance.