Precious stone measure alludes to the breadth of a round-cut jewel. It would be ideal if you note that the table appears the inexact sizes of jewels weighing from 0.2 to 15 carats, comparing to the cut bunch “A”. The estimate of a precious stone depends not as it were on weight, but too on the extents and symmetry of the cut. Precious stones are made by hand, so they can have the same weight and diverse sizes. See precious stones at a deal cost here gsi diamond grading