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".
Garnet (Pyrope, Rhodolite, Almandine, Spessartite, Grossular, Demantoid, Tsavorite)
Birdie (CHECK75.JRG)
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
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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