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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".

By Jeff R. Graham, updated on

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

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