A Guide to Diamond Carat Weight

Diamond carat weight is a measure of the size or mass of a diamond. It is one of the four essential factors determining a diamond's quality, along with cut, colour, and clarity, typically referred to as the 4Cs. The term carat weight began with carob seeds when early gem traders used these small, uniform seeds as counterweights in their balance scales. 

This Graff Guide provides a comprehensive analysis of diamond carat weight, including its definition, the importance of carat weight in selecting a diamond, and an overview of the carat weight scale.

What is a diamond carat?

Carat is the unit of measurement used to describe a diamond’s weight and is equal to 200 milligrams or 0.2 grams. Every Graff diamond is a true masterpiece, from perfectly proportioned stones of less than one carat to extraordinary gems weighing over 100 carats, such as the Graff Lesedi La Rona. 

What is the diamond carat weight scale?

The diamond carat weight scale is used to measure the weight of a diamond, with each carat consisting of 100 points. For example, a 0.5 carat diamond is equivalent to 50 points, while a 1 carat diamond is equivalent to 100 points. Carat weight can vary significantly from fractions of a carat to hundreds of carats. 

Less than 0.5 carats: Diamonds of 0.5 carats and less are typically used as accent stones in jewellery; for example, a 0.25 carat diamond may be used as a side stone in an engagement ring. 

From 0.5 to 3 carats: This carat range is a popular size for engagement rings and other fine jewellery pieces. A 1 carat diamond is often used as a benchmark for the centre stone within an engagement ring. 

From 5 carats upwards: Diamonds weighing 5 carats and above are considered rare and are often incorporated into high jewellery pieces.