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Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Atlas (MC65.JRG)
By Jeff R. Graham
Copyright 2002
87.6% Light Return
Angles for R.I. = 1.62
57 facets + 12 facets on girdle = 69
2-fold, mirror-image symmetry
96 index
L/W = 1.330 T/W = 0.598 T/L = 0.449
P/W = 0.555 C/W = 0.230
H/W = (P+C)/W+0.02 = 0.804
P/H = 0.690 C/H = 0.286
Vol./W^3 = 0.400Addition # 7 - This is great for medium saturated materials. It works well in Garnet, Sapphire and man-made materials with no changes. Note: I rough in P1, P2, P3 at 41.64 and then cut the other angles on a finer lap.

Random - Cosine - ISO
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