Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Crush (B36.JRG)
By Jeff R. Graham
Copyright 2001
88.1% Light Return
Angles for R.I. = 1.62
51 facets + 10 facets on girdle = 61
2-fold, mirror-image symmetry
96 index
L/W = 1.396 T/W = 0.921 T/L = 0.660
P/W = 0.586 C/W = 0.169
H/W = (P+C)/W+0.02 = 0.774
P/H = 0.756 C/H = 0.218
Vol./W^3 = 0.451
Addition # 5 – This needs a preform, but does not have a lot of facets and cuts pretty fast. It is really a “Money Cut”… This works in R.I. 1.62 to 1.93 with no changes.
Random – Cosine – ISO
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.
