Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Afghan Ice (DOME23.JRG)
By Jeff R. Graham
Copyright 2007
75.4% Light Return
Angles for R.I. = 1.62
73 facets + 8 facets on girdle = 81
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.329 T/L = 0.329 P/W = 0.438 C/W = 0.326
H/W = (P+C)/W+0.02 = 0.785 P/H = 0.559 C/H = 0.416
Vol./W^3 = 0.290
PAVILION
CROWN
Addition # 13 – Cut this in refractive indexes 1.62 to 2.14 with no changes. This is designed for light to medium saturated materials. It is specifically designed for bubble gum pink rough and to help intensify the color.
Detailed faceting instructions by Jeff Graham available at The Rock Peddler