Faceting Design Diagram: Viking’s Luck – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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

Viking’s Luck (CHECK71.JRG)
By Jeff R. Graham
Copyright 2003
82.7% Light Return
Angles for R.I. = 1.62
47 facets + 8 facets on girdle = 55
2-fold, mirror-image symmetry
96 index
L/W = 1.602 T/W = 0.515 T/L = 0.322
P/W = 0.436 C/W = 0.262
H/W = (P+C)/W+0.02 = 0.717
P/H = 0.607 C/H = 0.365
Vol./W^3 = 0.516

Addition # 8 – This is not very easy to cut, but after you have done it once, it’s not hard the next time. The L/W is not critical but should be close. Cut In refractive indexes 1.62 tp 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.