Penta Dome: Faceting Design Diagram

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


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

Penta dome Jeff Graham Facet Design 1Penta dome Jeff Graham Facet Design 2

Penta Dome (DOME34.JRG)
By Jeff R. Graham
Copyright 2007
82.4% Light Return
Angles for R.I. = 1.62
91 facets + 9 facets on girdle = 100
9-fold, mirror-image symmetry
72 index
L/W = 1.015 T/W = 0.274 T/L = 0.270 P/W = 0.403 C/W = 0.370
H/W = (P+C)/W+0.02 = 0.793 P/H = 0.508 C/H = 0.466
Vol./W^3 = 0.279



Addition # 13 - Cut in refractive indexes 1.62 to 2.14 with no changes. This is ideal for lightly saturated materials. It cuts easily and is not difficult. This is very good for pale saturated Afghan Tourmaline.

Penta dome Jeff Graham Facet Design 3

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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