Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Dome Brilliant (DOME41.JRG)
By Jeff R. Graham
Copyright 2007
81.6% Light Return
Angles for R.I. = 1.62
85 facets + 12 facets on girdle = 97
12-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.262 T/L = 0.262 P/W = 0.405 C/W = 0.419
H/W = (P+C)/W+0.02 = 0.843 P/H = 0.480 C/H = 0.496
Vol./W^3 = 0.310
PAVILION
CROWN
Addition # 13 – Cut in refractive indexes 1.62 to 2.14 with no changes. This is designed for pale to lightly saturated material and is ideal for nodules. It is not hard to cut, but there are quite a few facets and it will take some time.
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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