Faceting Design Diagram: Gentleman’s Choice – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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

Gentleman’s Choice (CHECK66.JRG)Nigerian Tourmaline
By Jeff R. Graham
Copyright 2003
89.6% Light Return
Angles for R.I. = 1.62
33 facets + 8 facets on girdle = 41
2-fold, mirror-image symmetry
96 index
L/W = 1.128 T/W = 0.456 T/L = 0.404
P/W = 0.495 C/W = 0.157
| H/W = (P+C)/W+0.02 = 0.671
P/H = 0.737 C/H = 0.233
Vol./W^3 = 0.327

Addition # 8 – Cut this in refractive indexes 1.62 to 2.14 with no changes. I designed this for a man’s ring, the shape is like the old style Masonic rings. I like this in about any material. It cuts easily and quickly.

 


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.