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.

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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…

 


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler


Jeff R. Graham

The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.

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