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Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Hint (MC112.JRG)
By Jeff R. Graham
Copyright 2006
75.8% Light Return
Angles for R.I. = 1.62
82 facets + 6 facets on girdle = 88
3-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.364 T/L = 0.364 P/W = 0.530
C/W = 0.198 H/W = (P+C)/W+0.02 = 0.748 P/H = 0.709 C/H = 0.265 Vol./W^3 = 0.236Addition # 12 - Cut this in refractive indexes 1.62 to 1.93 (79.7%) with no changes. This is designed for light materials and is brighter than the ray trace indicates. The crown can be cut in a different order.

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