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".
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
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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