CORRELATION OF DIFFERENT GRADING SYSTEMS

Comparison of different grading systems indicates that all of them are based on the evaluation of the four basic parameters: weight, color, clarity, and cut quality. The differences of the systems are in the method of evaluation. This especially concerns color, clarity, and cut. Non-Russian systems should be compared to one another and to the Russian grading system.
Most popular international grading system
Color
Clarity
Two-dimensional probability table to convert diamond clarity values from GIA system to TU
Two-dimensional probability table to convert diamond clarity values from TU system to GIA
Cut quality