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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 = 0.253Addition # 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
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