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Darhla: 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 "Darhla".

By Jeff R. Graham, updated on

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

Jeff Graham Faceting Design Jeff Graham Faceting Design

Darhla (MIR76.JRG)
By Jeff R. Graham
Copyright 2005
91.4% Light Return
Angles for R.I. = 1.62
41 facets + 10 facets on girdle = 51
5-fold, mirror-image symmetry
80 index
L/W = 1.051 T/W = 0.287 T/L = 0.273 P/W = 0.433 C/W = 0.238
H/W = (P+C)/W+0.02 = 0.691 P/H = 0.627 C/H = 0.344
Vol./W^3 = 0.217

PAVILION

CROWN

Addition # 10 - Cut in refractive indexes 1.62 to 2.14 with no changes. This is very nice and works well in about any saturation. I tend to prefer light to medium saturated stones and I like it in Tourmaline. It is a great Topaz cut.

 Jeff Graham Faceting Design

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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