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


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

Flutter (CHECK79.JRG)
By Jeff R. Graham
Copyright 2003
81.5% Light Return
Angles for R.I. = 1.62
35 facets + 12 facets on girdle = 47
2-fold, mirror-image symmetry
96 index
L/W = 1.200 T/W = 0.349 T/L = 0.291
P/W = 0.436 C/W = 0.230
H/W = (P+C)/W+0.02 = 0.686
P/H = 0.636 C/H = 0.335
Vol./W^3 = 0.234

Addition # 8 – Cut in refractive indexes 1.62 to 2.14 (86.4%) with no changes. This cuts easily with no real surprises.

 

 

 


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.