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

Two Spin Star (QTZ29.JRG)
By Jeff R. Graham
Copyright 1994
92.8% Light Return
Angles for R.I. = 1.54
30 facets + 6 facets on girdle = 36
6-fold symmetry
96 index
L/W = 1.155 P/W = 0.450 C/W = 0.164
H/W = (P+C)/W+0.02 = 0.635
P/H = 0.709 C/H = 0.259
Vol./W^3 = 0.215

Gram Book 1 - This design cuts easy and fast. When you get to C3 use a fine lap and cut gently. It is a nice design for about any material and I usually cut it in 4-8mm sizes. I designed it for earrings. On larger stones a table should be cut to meet C2,C3. I recommend this because as the stone gets larger there is a “hole” at the apex (look at the ray trace). Cut in refractive index 1.54 to 2.14 (86.5%) with no changes.

 

 

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