Diamond carat weight is the measurement of how much a diamond weighs. A metric ‘carat’ is defined as 200 milligrams, about as heavy as a paperclip.
Each carat can be subdivided into 100 ‘points’, allowing very precise measurements to the hundredth decimal place. A jeweller may describe the weight of a diamond below one carat by its ‘points’ alone, e.g. a 0.25 carat diamond may be referred to as a ‘25 pointer.’ Diamond weights greater than one carat are expressed in carats and decimals.
A 1.08 carat stone would be described as ‘one point oh eight carats.’
All else being equal, diamond price increases with diamond carat weight because larger diamonds are more rare and more desirable. But two diamonds of equal carat weight can have very different values (and prices) depending on three other factors of the diamond 4Cs: Clarity, Colour, and Cut. A phenomenon known as ‘fluorescence’ could also affect the value and appearance of a diamond.
It is important to remember that a diamond’s value is determined using all of the 4Cs in addition to its fluorescence, not just the carat weight.