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".

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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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