Diamond “C”: Faceting Design Diagram
Detailed information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Diamond "C".
Garnet (Pyrope, Rhodolite, Almandine, Spessartite, Grossular, Demantoid, Tsavorite)
Diamond "C" (GNETP29.JRG)
By Jeff R. Graham
Copyright 1996
90.3% Light Return
Angles for R.I. = 1.73
57 facets + 10 facets on girdle = 67
2-fold, mirror-image symmetry
96 index
L/W = 1.290 T/W = 0.557 T/L = 0.432
P/W = 0.406 C/W = 0.189
H/W = (P+C)/W+0.02 = 0.614
P/H = 0.660 C/H = 0.307
Vol./W^3 = 0.305
Gram Book 1 - This is a little tough to cut, but well worth it. The P7 & P9 meet at an apex and might need to be cheated a little bit. As long as they are close the P10 will cover them, good for darker material, 2-12cts. This works in man-made Sapphire and Spinel.
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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