Ideal crown height for princess cut

[Jeff]

I''m looking for a .90-.99ct princess cut diamond with Table 62-68% and Depth 64%-70%. I wanted to know what crown height% would be the most ideal. I saw the AGA scale which says 9-10%, but have heard from many other people it''s best in the 11-15% range for maximum light return. Please help if you have experience with Princess cuts.
Thank you,
Jeff

 

[RockDoc]

The suggested proportions for many fancy shaped diamonds to not always equal superior light return.

The proportions are only about 30% reliable. I have seen 1a stones that have less than excellent light return, and some that have lousy numbers that look great.

There is a lot more to this than table, depth and crown height.

As an initial sort tool these parameters may be helpful - but they are no guarantee of the quality of the light return of a fancy shape.

I have seen stones with 9% that are really good and I've seen good and bad with the higher percentages. A lot also depends on the pavilion angle, quadrant equalness and symmetry as well as the crown angle. There are no set proportions, that you should totally rely on.

If you think you've found a stone that might be the one you want, get it checked by an expert to make sure it is the stone you want.

Rockdoc

 

[barry]

Crown height is one ingredient that goes into the mix
and is really a function of crown angle.
The other ingredients are table %, pavillion angle,
lower quadrant angle, star facets, and angle
and length of the lower girdle facets.
Various combinations of these will give you
a great looking Princess Cut diamond. You can
therefore have two stones with very similar specs
that differ significantly on light output and
extent of light leakage. "Numbers" alone are not
a guarantee.

Barry
www.superbcert.com