Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Glitter Mine (MC86.JRG)
By Jeff R. Graham
Copyright 2003
85.9% Light Return
Angles for R.I. = 1.62
133 facets + 8 facets on girdle = 141
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.452 T/L = 0.452 P/W = 0.437
C/W = 0.185 H/W = (P+C)/W+0.02 = 0.642 P/H = 0.681 C/H = 0.288 Vol./W^3 = 0.205
PAVILION
CROWN
Addition # 12 – Cut in refractive indexes 1.62 to 2.14 (88.2) with no changes. This is designed for a large stone and works well in light to medium saturated colors. This takes a fair amount of cutting, but is not hard to cut. Rough in the table before cutting the stars, it makes the meets easier.
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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