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Primal Construct: Faceting Design Diagram


Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that prese

By Jeff R. Graham, updated on

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

Primal Construct (MIR30.JRG)
By Jeff R. Graham
Copyright 2004
88.2% Light Return
Angles for R.I. = 1.62
45 facets + 8 facets on girdle = 53
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.368 T/L = 0.368
P/W = 0.435 C/W = 0.229
H/W = (P+C)/W+0.02 = 0.684
P/H = 0.635 C/H = 0.335
Vol./W^3 = 0.259

Addition # 9 - This cuts a very bright stone and works well in medium saturated materials and, in particular, Garnets. This cuts fast and I prefer it in a large size stone. It makes excellent earrings, cut in refractive indexes 1.62 to 1.76 with no changes.

 


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Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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