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.


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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