Standard Round Brilliant with 16 Fold Symmetry
GemCad Derived Rendering by Bob Keller Bob Keller

SRB Variation with 16 Fold Symmetry
SRB Variation with 16 Fold Symmetry
Angles for R.I. = 1.54 113 facets + 32 facets on girdle = 145
16-fold, mirror-image symmetry 64 index
L/W = 1.000 T/W = 0.629 T/L = 0.629 P/W = 0.442 C/W = 0.109 H/W = (P+C)/W+0.02 = 0.572 P/H = 0.774 C/H = 0.191
Vol./W^3 = 0.186 Brightness at 0 degrees tilt for R.I. = 1.54
COS = 89.8% ISO = 93.8%
Pavilion
pb 42.00 01-03-05-07-09-11-13-15-17-19-21-23-25-27-29-31-
33-35-37-39-41-43-45-47-49-51-53-55-57-59-61-63
Cut to temporary center point
g 90.00 01-03-05-07-09-11-13-15-17-19-21-23-25-27-29-31-
33-35-37-39-41-43-45-47-49-51-53-55-57-59-61-63
Cut to meet pb
pm 41.50 64-04-08-12-16-20-24-28-32-36-40-44-48-52-56-60 Cut to meet pb,g
Crown
cb 32.00 01-03-05-07-09-11-13-15-17-19-21-23-25-27-29-31-
33-35-37-39-41-43-45-47-49-51-53-55-57-59-61-63
Cut to meet g - level girdle
cm 30.50 64-04-08-12-16-20-24-28-32-36-40-44-48-52-56-60 Cut to meet cb,g
s 25.00 02-06-10-14-18-22-26-30-34-38-42-46-50-54-58-62 Cut to meet cb,cm
t 0.00 Table Cut to meet s,cm
This variation of the SRB doubles the number of facets in each course by increasing the symmetry from 8 fold to 16 fold. Increasing the number of facets increases the scintillation and is a way of scaling up the SRB to work with larger stones. Note that this variation is cut with a 64 index.


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