There is no consensus on this issue today.
There is a set of Tolkowsky proportions:
53% Table
34.5° crown angle
40.75° pavilion angle
Knife edge girdle.
. AGS currently is using Firescope for developing cut grading system for fancy shaped diamonds.
is also working on their cut grading system based on Brilliancescope measurements.
Today, several serious labs including Moscow State University and GIA are developing their own cut grading systems.

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