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Quartz (Amethyst, Citrine, Ametrine, Smokey, Rose)

8 Round Brilliant (QTZ2.JRG) 5.32 carat Tourmaline
By Jeff R. Graham
Copyright 1993
78.5% Light Return
Angles for R.I. = 1.54
57 facets + 16 facets on girdle = 73
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.490 T/L = 0.490
P/W = 0.435 C/W = 0.168
H/W = (P+C)/W+0.02 = 0.623
P/H = 0.698 C/H = 0.270
Vol./W^3 = 0.226

Addition # 1 - This is a pretty standard round brilliant, a nice stone in any size and easy to cut. The crown at 42 degrees is as high as you can go and still have good light return in low R.I. materials. Cut in refractive indexes 1.54 to 1.93 (92.2%) with no changes.

 

 


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