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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"

By Jeff R. Graham, updated on

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

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