Faceting Design Diagram: Ten To Six – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite

Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)

Ten To Six (CHECK27.JRG)
By Jeff R. Graham
Copyright 2001
86.1% Light Return
Angles for R.I. = 1.62
57 facets + 6 facets on girdle = 63
6-fold, mirror-image symmetry
96 index
L/W = 1.155 T/W = 0.299 T/L = 0.259
P/W = 0.493 C/W = 0.213
H/W = (P+C)/W+0.02 = 0.726
P/H = 0.679 C/H = 0.293
Vol./W^3 = 0.292

Addition # 6 – This can be cut in refractive indexes 1.62 to 1.93 (88.7%) with no changes. The crown is a bit different, notice that the C2, C3 do not meet the girdle. The important thing you need to do is split the checks evenly to meet C4,C5 and line them up as you go around. This is fun to cut in about any material.

Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

Gram Faceting Archive of Information
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.