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Two Spin Star : Faceting Design Diagram


Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Two Spin Star".

By Jeff R. Graham, updated on

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

Two Spin Star (QTZ29.JRG) 2.15 carat Iolite
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.

 


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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