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Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Tourmaline 20 (MC32.JRG)
By Jeff R. Graham
Copyright 1998
83.6% Light Return
Angles for R.I. = 1.62
43 facets + 8 facets on girdle = 51
2-fold, mirror-image symmetry
96 index
L/W = 2.000 T/W = 1.354 T/L = 0.677
P/W = 0.493 C/W = 0.181
H/W = (P+C)/W+0.02 = 0.694
P/H = 0.710 C/H = 0.261
Vol./W^3 = 0.744Addition # 4 - If you are cutting in Tourmaline, be sure that the "c" axis is close in color to the a/b or this design will get muddy. The keel on this is harder than it looks, it works well in Topaz, 1-12cts. Cut this in R.I. 1.62 to 1.76 (82.4%) without changes.

Random - Cosine - ISO
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