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".

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HomeLearning CenterJewelry and LapidaryGemstone Faceting Diagrams and Technical Cutting InformationShoal: Faceting Design Diagram
By Jeff R. Graham

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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