Signature #3: Faceting Design Diagram
Helpful tips, details and guide on Faceting Designs. Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Signature #3"
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Signature #3 (B15.JRG)
By Jeff R. Graham
Copyright 2000
89.9% Light Return
Angles for R.I. = 1.62
77 facets + 12 facets on girdle = 89
2-fold, mirror-image symmetry
96 index
L/W = 1.330 T/W = 0.870 T/L = 0.654
P/W = 0.612 C/W = 0.175
H/W = (P+C)/W+0.02 = 0.807
P/H = 0.759 C/H = 0.217
Vol./W^3 = 0.491
Addition # 5 - This is one of my favorite rectangle cushions to cut (that's why it's a Signature cut). It is well worth the trouble. This design is very bright, and I find that it works well in medium colored material. This cuts in R.I. 1.62 to 1.76 (87.5%) with no changes.
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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