Np-Point : Faceting Design Diagram
Tips, details, and a guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Np-Point".
Quartz (Amethyst, Citrine, Ametrine, Smokey, Rose)
Np-Point (QTZ48.JRG)
By Jeff R. Graham
Copyright 1996
73.6% Light Return
Angles for R.I. = 1.54
67 facets + 9 facets on girdle = 76
3-fold, mirror-image symmetry
96 index
L/W = 1.016 T/W = 0.542 T/L = 0.534
P/W = 0.430 C/W = 0.227
H/W = (P+C)/W+0.02 = 0.677
P/H = 0.635 C/H = 0.336
Vol./W^3 = 0.253
Addition # 1 - The P7 facets meet at the girdle only. It's important to cut them evenly at the correct angle. The steps on the crown can be varied if you want, adjust the C7's. Cut in refractive indexes 1.54 to 1.93 (80.2%) with no changes. This design is fairly hard to cut, 2-12cts.
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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