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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".

By Jeff R. Graham, updated on

Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)

Apature Jeff Graham Facet Design 1Apature Jeff Graham Facet Design 2

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.

Apature Jeff Graham Facet Design 3

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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