Hexactly
GemCad Ray Traces for RI = 1.72
Random Model Cosine Model ISO Model
Hexactly
Designed by Bob Keller 12-00 Bob Keller
An easy to cut meetpoint design for spinel, corundum, garnet.
Angles for R.I. = 1.72 73 facets + 6 facets on girdle = 79
6-fold, mirror-image symmetry 96 index
L/W = 1.155 T/W = 0.654 T/L = 0.567 P/W = 0.502 C/W = 0.209 H/W = (P+C)/W+0.02 = 0.731 P/H = 0.687 C/H = 0.286
Vol./W^3 = 0.311 Brightness at 0 degrees tilt for RI = 1.72
COS = 81.4 ISO = 90.3
Pavilion
g1 90.00 96-16-32-48-64-80 Cut to equal depth - establish size
2 65.00 96-16-32-48-64-80 match g1 - make level girdle
3 41.00 08-24-40-56-72-88 meet g1,2 - culet
4 43.13 06-10-22-26-38-42-54-58-70-74-86-90 meet g1,2,3
5 39.61 05-11-21-27-37-43-53-59-69-75-85-91 meet 2,4 - culet
Crown
a 55.00 96-16-32-48-64-80 match g1 - make level girdle
b 45.00 02-14-18-30-34-46-50-62-66-78-82-94 meet g1,a
c 36.48 07-09-23-25-39-41-55-57-71-73-87-89 meet g1,a,b
d 34.00 08-24-40-56-72-88 meet b,c
t 0.00 Table meet b,c,d


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Perfect Transfer Index

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