OPLC Faceters Companion

Standard Round Brilliant with Doubled Mains and Stars
GemCad Derived Rendering by Bob Keller

SRB Variation with Doubled Mains and Stars

Angles for R.I. = 1.54 81 facets + 16 facets on girdle = 97

16-fold, mirror-image symmetry 96 index

L/W = 1.000 T/W = 0.618 T/L = 0.618 P/W = 0.442 C/W = 0.134 H/W = (P+C)/W+0.02 = 0.596 P/H = 0.742 C/H = 0.224

Vol./W^3 = 0.197 Brightness at 0 degrees tilt for R.I. = 1.54
COS = 64.4% ISO = 68.1%

Pavilion

pb 42.50 03-09-15-21-27-33-39-45-51-57-63-69-75-81-87-93 Cut to temporary center point

g 90.00 03-09-15-21-27-33-39-45-51-57-63-69-75-81-87-93 Cut to meet pb

pm 41.50 96-06-12-18-24-30-36-42-48-54-60-66-72-78-84-90 Cut to meet pb,g

Crown

cb 38.00 03-09-15-21-27-33-39-45-51-57-63-69-75-81-87-93 Cut to meet g - level girdle

cm 35.00 96-06-12-18-24-30-36-42-48-54-60-66-72-78-84-90 Cut to meet cb,g

s 27.00 03-09-15-21-27-33-39-45-51-57-63-69-75-81-87-93 Cut to meet cb,cm

t 0.00 Table Cut to meet s,cm

This variation of the SRB doubles the number of main and star facets in each course. Note that in this variation the symmetry increases from 8 fold to 16 fold - there are 16 each pavilion main, pavilion break, girdle, crown break, crown main and star facets. Increasing the number of facets increases the scintillation and is a way of scaling up the SRB to work with larger stones.

The SRB with Doubled Mains and Stars Design File is available for GemCad users.

SRB Variation with Doubled Mains and Stars
Angles for R.I. = 1.54	81 facets + 16 facets on girdle = 97
16-fold, mirror-image symmetry	96 index
L/W = 1.000 T/W = 0.618 T/L = 0.618 P/W = 0.442 C/W = 0.134	H/W = (P+C)/W+0.02 = 0.596 P/H = 0.742 C/H = 0.224
Vol./W^3 = 0.197	Brightness at 0 degrees tilt for R.I. = 1.54 COS = 64.4% ISO = 68.1%

Pavilion
pb	42.50	03-09-15-21-27-33-39-45-51-57-63-69-75-81-87-93	Cut to temporary center point
g	90.00	03-09-15-21-27-33-39-45-51-57-63-69-75-81-87-93	Cut to meet pb
pm	41.50	96-06-12-18-24-30-36-42-48-54-60-66-72-78-84-90	Cut to meet pb,g
Crown
cb	38.00	03-09-15-21-27-33-39-45-51-57-63-69-75-81-87-93	Cut to meet g - level girdle
cm	35.00	96-06-12-18-24-30-36-42-48-54-60-66-72-78-84-90	Cut to meet cb,g
s	27.00	03-09-15-21-27-33-39-45-51-57-63-69-75-81-87-93	Cut to meet cb,cm
t	0.00	Table	Cut to meet s,cm
This variation of the SRB doubles the number of main and star facets in each course. Note that in this variation the symmetry increases from 8 fold to 16 fold - there are 16 each pavilion main, pavilion break, girdle, crown break, crown main and star facets. Increasing the number of facets increases the scintillation and is a way of scaling up the SRB to work with larger stones.

Return to CD Index