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Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Crown Star (CHECK14.JRG)
By Jeff R. Graham
Copyright 2001
88% Light Return
Angles for R.I. = 1.62
53 facets + 12 facets on girdle = 65
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.373 T/L = 0.373
P/W = 0.442 C/W = 0.180
H/W = (P+C)/W+0.02 = 0.642
P/H = 0.688 C/H = 0.281
Vol./W^3 = 0.259Addition # 6 - Cut this in refractive indexes 1.62 to 1.92 with no changes. This makes a very bright and sparkly stone. Notice that the pavilion facets P5, P6 are creating a lot of movement.

Random - Cosine - ISO
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