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Shoal: 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 "Shoal".

By Jeff R. Graham, updated on

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

Shoal (CHECK36.JRG)
By Jeff R. Graham
Copyright 2001
92% Light Return
Angles for R.I. = 1.54
57 facets + 12 facets on girdle = 69
2-fold, mirror-image symmetry
120 index
L/W = 1.313 T/W = 0.384 T/L = 0.293
P/W = 0.571 C/W = 0.210
H/W = (P+C)/W+0.02 = 0.800
P/H = 0.713 C/H = 0.262
Vol./W^3 = 0.420

Addition # 6 - This is 93.9% in refractive indexes 1.62, can be cut in any material with no changes (1.93 is 92.4%). This is pretty quick to cut and not difficult, although the crown can take some lining up.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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