Faceting Design Diagram: Hexed “T” – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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

Hexed “T” (TLINE23.JRG)
By Jeff R. Graham
Copyright 1995
81.7% Light Return
Angles for R.I. = 1.62
61 facets + 10 facets on girdle = 71
2-fold, mirror-image symmetry
96 index
L/W = 1.203 T/W = 0.606 T/L = 0.503
P/W = 0.451 C/W = 0.218
H/W = (P+C)/W+0.02 = 0.689
P/H = 0.655 C/H = 0.316
Vol./W^3 = 0.348

Gram Book 1 – The P9(G) can be cut in after P4(G) if you want to. The P8,P10 facets only meet at the girdle, so it’s important that you make sure that the girdle is level. Cut in any material, 1-12cts. This works well in Topaz, and Peridot.

 

 


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.