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12 Swirl: Faceting Design Diagram


Details and information on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts and facets suitable for different gems.

By Jeff R. Graham, updated on

Garnet (Pyrope, Rhodolite, Almandine, Spessartite, Grossular, Demantoid, Tsavorite)

12 Swirl (GNETA2.JRG)
By Jeff R. Graham
Copyright 1993
91.9% Light Return
Angles for R.I. = 1.78
85 facets + 12 facets on girdle = 97
12-fold symmetry
96 index
L/W = 1.000 T/W = 0.362 T/L = 0.362
P/W = 0.369 C/W = 0.180
H/W = (P+C)/W+0.02 = 0.569
P/H = 0.649 C/H = 0.316
Vol./W^3 = 0.203

Addition # 3 - A variation of the 8-Swirl, Almandite Garnet, cuts like the "8" and makes a nice stone, 1-10ct. This works well in man made materials, like YAG, Sapphire and Spinel. I prefer it in lighter colors, it is nice in Zircons too…

 


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Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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