Step'in "C": Faceting Design Diagram


Successful tips, details and guide on Faceting Designs. Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Step'in C"

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

Jeff Graham Facet Designq

 Jeff Graham Facet Design

Step'in "C" (MIR77.JRG)
By Jeff R. Graham
Copyright 2005
88.8% Light Return
Angles for R.I. = 1.62
29 facets + 8 facets on girdle = 37
2-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.257 T/L = 0.257 P/W = 0.438
C/W = 0.229 H/W = (P+C)/W+0.02 = 0.687 P/H = 0.637 C/H = 0.334 Vol./W^3 = 0.320

PAVILION

CROWN

Addition # 10 - Cut in refractive indexes 1.62 to 1.76 with no changes. This is designed for dark axis "c" Tourmaline. It is easy to cut and works well. It has step/checker reflection. The crown can be lowered to 30 degrees for very dark material.

Jeff Graham Facet Design

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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