Asterism: Faceting Design Diagram

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

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.

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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