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


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

Piller (B29.JRG) 10.18 carat Nigerian pink Tourmaline
By Jeff R. Graham
Copyright 2001
82.7% Light Return
Angles for R.I. = 1.62
55 facets + 8 facets on girdle = 63
2-fold, mirror-image symmetry
96 index
L/W = 1.228 T/W = 0.830 T/L = 0.676
P/W = 0.539 C/W = 0.166
H/W = (P+C)/W+0.02 = 0.726
P/H = 0.743 C/H = 0.229
Vol./W^3 = 0.316

Addition # 5 – Notice that the C2 on the crown is left for taking up slack if your L/W is slightly off. This can be cut in almost any R.I. with no changes (88.2% in 1.76). It’s fast to cut and nice in almost any good colored 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.