Rainbow II: Faceting Design Diagram


Helpful tips, details and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Rainbow II"

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

Rainbow II (B16.JRG)
By Jeff R. Graham
Copyright 1999
89% Light Return
Angles for R.I. = 1.76
65 facets + 16 facets on girdle = 81
2-fold, mirror-image symmetry
96 index
L/W = 1.500 T/W = 1.011 T/L = 0.674
P/W = 0.662 C/W = 0.200
H/W = (P+C)/W+0.02 = 0.882
P/H = 0.751 C/H = 0.226
Vol./W^3 = 0.518

Addition # 5 - This is very nice in a light colored Sapphire (if you are lucky enough to find some) and works in man-made material as well. The breaks are a bit steeper than I prefer (this is a 1.50 L/W stone...), but should set with no problems. Light colored Zircons work great in this design.


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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