Trig: Faceting Design Diagram

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


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

Trig (CHECK12.JRG) 3.03 carat Aquamarine
By Jeff R. Graham
Copyright 2001
83.7% Light Return
Angles for R.I. = 1.54
52 facets + 12 facets on girdle = 64
3-fold, mirror-image symmetry
96 index
L/W = 1.013 T/W = 0.239 T/L = 0.236
P/W = 0.391 C/W = 0.199
H/W = (P+C)/W+0.02 = 0.609
P/H = 0.641 C/H = 0.326
Vol./W^3 = 0.192

Addition # 6 - Notice that the crown on this design is deep to help darken light colored material. The only light loss is at the edge of the girdle, where prongs will cover it.

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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