Faceting Design Diagram: Jerico – Tourmaline, Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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

Jerico_facet_Design_1

Jeff Graham Facet Design

Jerico (MIR57.JRG)
By Jeff R. Graham
Copyright 2005
89.3% Light Return
Angles for R.I. = 1.62
41 facets + 8 facets on girdle = 49
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.250 T/L = 0.250 P/W = 0.466
C/W = 0.205 H/W = (P+C)/W+0.02 = 0.692 P/H = 0.674 C/H = 0.297 Vol./W^3 = 0.259

Addition # 10 – Cut in refractive indexes 1.62 to 1.93 with no changes. This has a lot of reflections in it and works best in a large stone with light saturation. This is quick and easy to cut. It is great for large earrings.

Jeff Graham Facet Design

 

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

Gram Faceting Archive of Information
This edited version of an article by the late Jeff Graham is part of a special archived informational series from Gram Faceting. Used with permission.