Prime Construct: Faceting Design Diagram

Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Prime Construct".


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

Jeff Graham Faceting DesignJeff Graham Faceting Design

Prime Construct (MIR75.JRG)
By Jeff R. Graham
Copyright 2005
86.5% Light Return
Angles for R.I. = 1.62
37 facets + 12 facets on girdle = 49
4-fold, mirror-image symmetry
80 index
L/W = 1.000 T/W = 0.491 T/L = 0.491 P/W = 0.450
C/W = 0.190 H/W = (P+C)/W+0.02 = 0.661 P/H = 0.681 C/H = 0.288 Vol./W^3 = 0.259



Addition # 10 - Cut in refractive indexes 1.62 to 1.76 with no changes. This is designed for light to medium saturated stones and is very nice. It is simple and fast to cut, but the flash is intense.

Jeff Graham Faceting Design

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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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