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Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Nigerian Pink (MC40.JRG)
By Jeff R. Graham
Copyright 1999
76.5% Light Return
Angles for R.I. = 1.62
52 facets + 15 facets on girdle = 67
3-fold, mirror-image symmetry
96 index
L/W = 1.016 T/W = 0.707 T/L = 0.696
P/W = 0.384 C/W = 0.163
H/W = (P+C)/W+0.02 = 0.567
P/H = 0.677 C/H = 0.288
Vol./W^3 = 0.198Addition # 4 - This is designed for light colored stones, it has a lot of sparkle and depth for improving dispersion and color. The light return on this is better than the ray trace says, and it has a very nice pattern, 1cts+. Cut this in R.I. 1.62 to 1.76 without changes.

Random - Cosine - ISO
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