Diamond weight is measured in carats. Each carat is divided into 100 points. So, a 50-point diamond is the equivalent of a half-carat diamond.
In general, more carats means a larger looking and more expensive diamond. But keep in mind that quality, not just size, determines a diamond’s value.
A large diamond that’s poorly cut will lack brilliance, making it far less appealing and valuable than a smaller diamond with a very good cut. 
