Faceting Design Diagram: Cut Corner Pent – Garnet – Pyrope, Rhodolite, Almandine, Spessartite, Grossular, Demantoid, Tsavorite


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

Cut Corner Pent (GNETP32.JRG)
By Jeff R. Graham
Copyright 1996
87.1% Light Return
Angles for R.I. = 1.73
66 facets + 10 facets on girdle = 76
5-fold, mirror-image symmetry
80 index
L/W = 1.051 T/W = 0.468 T/L = 0.445
P/W = 0.436 C/W = 0.197
H/W = (P+C)/W+0.02 = 0.653
P/H = 0.668 C/H = 0.301
Vol./W^3 = 0.235

Gram Book 1 – Note 80 index. This cuts easy in about any material, 1-6cts. This works well in man-made Sapphire and Spinel. I especially like it in Rhodolite Garnet 2-3cts. Cut in refractive indexes 1.73 to 2.14 with no changes.


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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