Fanned Triangle: Faceting Design Diagram

Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Fanned Triangle".


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

Fanned Triangle (QTZ40.JRG)
By Jeff R. Graham
Copyright 1994
88.3% Light Return
Angles for R.I. = 1.54
52 facets + 15 facets on girdle = 67
3-fold, mirror-image symmetry
96 index
L/W = 1.028 T/W = 0.303 T/L = 0.295
P/W = 0.392 C/W = 0.213
H/W = (P+C)/W+0.02 = 0.625
P/H = 0.627 C/H = 0.341
Vol./W^3 = 0.211

Addition # 1 - This design is fairly hard to cut and takes some work and attention to detail. Cut in refractive indexes 1.54 to 1.93 with no changes. Light material makes the best stone, 1-12cts.

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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