Faceting Design Diagram: Tri-Angled Triangle – Garnet – Pyrope, Rhodolite, Almandine, Spessartite, Grossular, Demantoid, Tsavorite


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

Tri-Angled Triangle (GNETP18.JRG)
By Jeff R. Graham
Copyright 1993
78.1% Light Return
Angles for R.I. = 1.73
61 facets + 9 facets on girdle = 70
3-fold, mirror-image symmetry
96 index
L/W = 1.071 T/W = 0.517 T/L = 0.483
P/W = 0.429 C/W = 0.193
H/W = (P+C)/W+0.02 = 0.642
P/H = 0.668 C/H = 0.301
Vol./W^3 = 0.217

Gram 1 – This stone has better light return than the 80% that it shows. It works best when it is cut in light material, 1-8cts. This works well in Spinel, Sapphire and YAG.


Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

About the author
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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