Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Winter Ice (DOME37.JRG)
By Jeff R. Graham
Copyright 2007
84.7% Light Return
Angles for R.I. = 1.62
85 facets + 6 facets on girdle = 91
6-fold, mirror-image symmetry
96 index
L/W = 1.155 T/W = 0.217 T/L = 0.188 P/W = 0.419 C/W = 0.404
H/W = (P+C)/W+0.02 = 0.843 P/H = 0.497 C/H = 0.479
Vol./W^3 = 0.342
PAVILION
CROWN
Addition # 13 – Cut in refractive indexes 1.62 to 2.14 with no changes. This is ideal for lightly saturated material and works well in about any material. This is not hard to cut and is very pretty.
Detailed faceting instructions by Jeff Graham available at The Rock Peddler