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Imperial: Faceting Design Diagram


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

By Jeff R. Graham, updated on

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

Imperial (GNETP24.JRG)
By Jeff R. Graham
Copyright 1995
85.2% Light Return
Angles for R.I. = 1.73
77 facets + 12 facets on girdle = 89
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.496 T/L = 0.496
P/W = 0.412 C/W = 0.212
H/W = (P+C)/W+0.02 = 0.644
P/H = 0.640 C/H = 0.329
Vol./W^3 = 0.281

Gram Book 1 - Make sure that the meets at C3,C4,C5 and the table (to be cut) are lined up. This design is a little hard to cut, but with a little work most cutters can handle it. Light material, like a Mali or Rose Malaya Garnet works best. This also works well in man-made Sapphires and Zircons.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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