Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Double Rose (DOME27.JRG)
By Jeff R. Graham
Copyright 2007
81% Light Return
Angles for R.I. = 1.62
121 facets + 8 facets on girdle = 129
16-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.319 T/L = 0.319 P/W = 0.438 C/W = 0.391
H/W = (P+C)/W+0.02 = 0.849 P/H = 0.516 C/H = 0.460
Vol./W^3 = 0.330
PAVILION
CROWN
Addition # 13 -Cut this in refractive indexes 1.62 to 2.14 with no changes. This is designed for light saturated color and a large stone is best. This is not hard to cut, other than is has a lot of facets.
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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