Faceting Design Diagram: Sheila – Tourmaline, Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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

Sheila Jeff Graham Facet Design Sheila Jeff Graham Facet Design

Sheila (MC113.JRG)
By Jeff R. Graham
Copyright 2002
79.2% Light Return
Angles for R.I. = 1.62
124 facets + 18 facets on girdle = 142
3-fold, mirror-image symmetry
96 index
L/W = 1.039 T/W = 0.459 T/L = 0.442 P/W = 0.506
C/W = 0.201 H/W = (P+C)/W+0.02 = 0.726 P/H = 0.696 C/H = 0.276 Vol./W^3 = 0.259

Addition # 12 – Cut in refractive indexes 1.62 to 2.14 (83.3%) with no changes. This is really nice in medium colored material and needs to be cut in a large size. This cuts faster than it looks.

Sheila Jeff Graham Facet Design

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.