Tiles
GemCad Ray Traces for RI = 1.70
Random Model Cosine Model 71.3 ISO Model 83.5
Tiles
Designed by Fred Van Sant November 2001
Rendered by Bob Keller
Angles for R.I. = 1.70+ 73 facets + 12 facets on girdle = 85
4-fold, mirror-image symmetry 120 index
L/W = 1.000 T/W = 0.2078 C/W = .1508 P/W = .5046 H/W = 0.6754
a/W = .311701 b/W = .273118 Brightness at 0 degrees tilt for RI = 1.70
COS = 71.3 ISO = 79.0
Pavilion
a 90.00 120-030-060-090 From preform
b 90.00 006-024-036-054-066-084-096-114 From preform
1 58.03 120-030-060-090 Match a, establish lower girdle line
2 53.75 006-024-036-054-066-084-096-114 Meet 1.a.b
3 41.00 015-045-075-105 Meet 2.b.b.2
4 41.00 120-030-060-090 Meet culet
5 46.01 008-022-038-052-068-082-098-112 Meet 3.2.b
6 43.42 120-030-060-090 Meet 1.2.5, 3.4.5
Crown
1 39.14 120-030-060-090 Match a, establish upper girdle line
2 43.22 006-024-036-054-066-084-096-114 Meet 1.a.b
3 37.54 002-028-032-058-062-088-092-118 Meet 1.a.b.2
4 22.32 015-045-075-105 Meet 2.b.b.2
5 16.73 005-025-035-055-065-085-095-115 Meet 3.2.4
6 16.20 120-030-060-090 Meet 1.3.5
7 12.00 120-030-060-090 Match 6 (step cut)
8 0.00 Any Table

On pavilion, advise cutting sets 1 and 2 at higher angle when making girdle line, and recut last to fit 5 and 6.

GemCad Ray Traces for RI = 1.70
Random Model Cosine Model 79.0 ISO Model 83.5

Alternate Pavilion
a 90.00 120-030-060-090 From preform
b 90.00 006-024-036-054-066-084-096-114 From preform
1 58.03 120-030-060-090 Match a, establish lower girdle line
2 53.75 006-024-036-054-066-084-096-114 Meet 1.a.b
3 41.00 015-045-075-105 Meet 2.b.b.2
4 42.11 120-030-060-090 Meet culet
5 46.01 008-022-038-052-068-082-098-112 Meet 3.2.b, 4.1.2

Alternate Pavilion: Same as above except set 6 is eliminated. Set 4 is extended to meet point where facets 1-2-5 meet. Set 4 angle is 42.11°.

Tiles Preform
pf1 39.28 120-030-060-090 Meet TCP
pf2 37.98 006-024-036-054-066-084-096-114 Meet TCP
a 90.00 120-030-060-090 Match pf1, establish size
b 90.00 006-024-036-054-066-084-096-114 Meet pf1.a.b


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