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Triple Star: Faceting Design Diagram


Helpful tips, details, and guide on Faceting Designs. Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Triple Star"

By Jeff R. Graham, updated on

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

Triple Star (TLINE14.JRG)
By Jeff R. Graham
Copyright 1993
78.5% Light Return
Angles for R.I. = 1.62
113 facets + 16 facets on girdle = 129
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.535 T/L = 0.535
P/W = 0.423 C/W = 0.185
H/W = (P+C)/W+0.02 = 0.628
P/H = 0.673 C/H = 0.295
Vol./W^3 = 0.221

Gram Book 1 - This design is good for a large stone 1-20cts, in light to medium material. It is not hard to cut, and it has a lot of sparkle. The star in the point of the Pavilion makes the table lively. Cut in refractive index 1.62 to 2.14 (89.5%) with no changes.

 


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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