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 (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
PAVILION
CROWN
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.
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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