3-6-3 Triangle: Faceting Design Diagram

Detailed information and guide on Faceting Designs. Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called 3-6-3 Triangle


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

Jeff R. Graham

The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.

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