Six Swifts
GemCad Ray Traces for RI = 1.72
Random Model Cosine Model ISO Model
Six Swifts
Designed by Bob Keller June 2001 Bob Keller
An Easy to Cut Twelve Sided Round
Angles for R.I. = 1.63 and up 55 facets + 12 facets on girdle = 67
6-fold, mirror-image symmetry 96 index
L/W = 1.000 T/W = 0.574 T/L = 0.574 P/W = 0.413 C/W = 0.176 H/W = (P+C)/W+0.02 = 0.610 P/H = 0.678 C/H = 0.289
Vol./W^3 = 0.200 Brightness at 0 degrees tilt for RI = 1.72
COS = 79.2 ISO = 87.8
Pavilion
g 90.00 04-12-20-28-36-44-52-60-68-76-84-92 Cut to equal depth, establish size
a 41.00 04-12-20-28-36-44-52-60-68-76-84-92 Match g, make level lower girdle line
b 39.58 96-16-32-48-64-80 Meet a.g, and at culet
Crown
1 42.46 04-12-20-28-36-44-52-60-68-76-84-92 Match g, make level upper girdle line
2 37.36 02-14-18-30-34-46-50-62-66-78-82-94 Meet g.1
3 39.57 08-24-40-56-72-88 Meet g.1
4 35.00 96-16-32-48-64-80 Meet g.1.2
t 0.00 Table Meet 2.3.4

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© Bob's Rock Shop Bob Keller