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


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.

 


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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