Asterism: Faceting Design Diagram


Detailed information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Asterism".

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

Asterism Jeff Graham Facet Design

Asterism Jeff Graham Facet Design

Asterism (MC108.JRG)
By Jeff R. Graham
Copyright 2006
78.6% Light Return Angles for
R.I. = 1.62
145 facets + 16 facets on girdle = 161
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.350 T/L = 0.350 P/W = 0.431
C/W = 0.206 H/W = (P+C)/W+0.02 = 0.657 P/H = 0.656 C/H = 0.314 Vol./W^3 = 0.211

PAVILION

CROWN

Addition # 12 - Cut this in refractive indexes 1.62 to 2.14 with no changes. This works well in light to medium saturated materials and it should be cut at least 10mm or larger. This is easy to cut and very bright.

Asterism Jeff Graham Facet 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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