Apature: 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 "Apature".
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Apature (DOME25.JRG)
By Jeff R. Graham
Copyright 2007
84% Light Return
Angles for R.I. = 1.62
161 facets + 16 facets on girdle = 177
16-fold symmetry
96 index
L/W = 1.000 T/W = 0.250 T/L = 0.250 P/W = 0.405 C/W = 0.361
H/W = (P+C)/W+0.02 = 0.786 P/H = 0.515 C/H = 0.460
Vol./W^3 = 0.275
PAVILION
CROWN
Addition # 13 - Cut this in refractive indexes 1.62 to 2.14 with no changes. This is designed for a large stone and light saturation. It is not hard to cut and is very interesting.
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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