Faceting Design Diagram: Est #1 – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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

Est #1 (TLINE51.JRG)
By Jeff R. Graham
Copyright 1998
81% Light Return
Angles for R.I. = 1.62
29 facets + 4 facets on girdle = 33
2-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.444 T/L = 0.444
P/W = 0.495 C/W = 0.139
H/W = (P+C)/W+0.02 = 0.654
P/H = 0.757 C/H = 0.212
Vol./W^3 = 0.336

Addition # 3 – This cuts like a pretty standard step cut. The only different thing about it is the high light return. Try it in a good med color tourmaline of about any color, 1-18cts. Can be cut as a rectangle any L/W, put the “c” axis on Tourmaline on the steep ends… Cut in refractive indexes 1.62 to 2.14 with no changes.


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.