Pent Mod “R”: Faceting Design Diagram

Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Pent Mod "R" ".


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

Pent Mod "R" (GNETP37.JRG)
By Jeff R. Graham
Copyright 1997
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

Addition # 2 - This design cuts easy, but watch how you cut the P6, P7. They alternate and both meet the P3 tier. This has a very nice flash, just about any Garnet will work, I prefer light colors. I like it in Rose Malaya Garnet, 1-6cts. 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

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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