Faceting Design Diagram: 3-6-3 Triangle – Quartz – Citrine, Amethyst, Ametrine, Smokey, Rose


Quartz (Amethyst, Citrine, Ametrine, Smokey, Rose)

3-6-3 Triangle (QTZ19.JRG)
By Jeff R. Graham
Copyright 1993
75.4% Light Return
Angles for R.I. = 1.54
52 facets + 9 facets on girdle = 61
3-fold, mirror-image symmetry
96 index
L/W = 1.053 T/W = 0.516 T/L = 0.490
P/W = 0.380 C/W = 0.188
H/W = (P+C)/W+0.02 = 0.588
P/H = 0.646 C/H = 0.320
Vol./W^3 = 0.187

Gram Book 1 – A nice shaped triangle that cuts fairly fast, and is good for about any material, 1-6cts. This works also well in Tourmaline and Topaz, I like it for earrings, in a medium color stone. Cut in refractive index 1.54 to 1.76 (77.5%) 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.