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Birdie: Faceting Design Diagram


Detailed information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Birdie".

By Jeff R. Graham, updated on

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

Birdie (CHECK75.JRG)Birdie in Mali Garnet
By Jeff R. Graham
Copyright 2003
84.3% Light Return
Angles for R.I. = 1.73
41 facets + 14 facets on girdle = 55
2-fold, mirror-image symmetry
96 index
L/W = 1.250 T/W = 0.292 T/L = 0.234
P/W = 0.455 C/W = 0.215
H/W = (P+C)/W+0.02 = 0.690
P/H = 0.659 C/H = 0.312
Vol./W^3 = 0.294

Addition # 8 - I designed this for a Mali Garnet, but it works well in any Garnet.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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