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".0
By Jeff R. Graham
73.6% Light Return
Angles for R.I. = 1.54
67 facets + 9 facets on girdle = 76
3-fold, mirror-image symmetry
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
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