Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Lilac Lace (DOME14.JRG)
By Jeff R. Graham
Copyright 2007
86.7% Light Return
Angles for R.I. = 1.62
61 facets + 6 facets on girdle = 67
6-fold, mirror-image symmetry
96 index
L/W = 1.155 T/W = 0.265 T/L = 0.230 P/W = 0.419
C/W = 0.266 H/W = (P+C)/W+0.02 = 0.705 P/H = 0.595 C/H = 0.377 Vol./W^3 = 0.256
Addition # 13 – Cut this in refractive indexes 1.62 to 2.14 with no changes. This works well in light to medium saturated stones. I like it in Rubellite and hot pink Tourmaline. The crown can take a bit of tweaking. NOTE: The C3 tier is just cut to eye and it can be varied slightly.
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
This edited version of an article by the late Jeff Graham is part of a special archived informational series from Gram Faceting. Used with permission.
