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


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

eff Graham Gemstone Facet Design

 Jeff Graham Gemstone Facet Design

 

Tumbler (MIR78.GJRG)
By Jeff R. Graham
Copyright 2005
80.8% Light Return
Angles for R.I. = 1.62
64 facets + 16 facets on girdle = 80
8-fold symmetry
96 index
L/W = 1.000 P/W = 0.435 C/W = 0.259
H/W = (P+C)/W+0.02 = 0.714 P/H = 0.609 C/H = 0.363
Vol./W^3 = 0.212

 

Addition # 10 – This is fast and fun to cut, the flash is really very pretty. I prefer this in light saturations. On large stones a table can be cut. Try this in some earrings, they are striking. This is a nice change from a round brilliant.

 


Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

About the author
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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