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Spinel (Red, Pink, Lavender, Green, Blue, Orange, Violet)

Square Star (SPINEL4.JRG)
By Jeff R. Graham
Copyright 1997
81.1% Light Return
Angles for R.I. = 1.71
89 facets + 16 facets on girdle = 105
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.557 T/L = 0.557
P/W = 0.413 C/W = 0.161
H/W = (P+C)/W+0.02 = 0.594
P/H = 0.695 C/H = 0.271
Vol./W^3 = 0.209

Addition # 3 - The C2,C3 steps are really the same and can be cut at one time, but I think it's easier to meet in two tiers. Easy to cut and works well in any nice color material 1-6cts. Cut in refractive indexes 1.71 to 2.14 (85.4%)with no changes.

 

 



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