Havilah Designer Jewellers

This is a measurement of the weight of a diamond.  One carat being equal to 100 points.  Although the size of a diamond would give an indication of its weight, this would not be exact, as the weight is influenced by the cut.  

The larger the diamond, the more rare it becomes, and therefore the more costly.  It is therefore understandable how a one carat diamond would cost much more than two half carat diamonds.