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".0
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
By Jeff R. Graham
78.6% Light Return Angles for
R.I. = 1.62
145 facets + 16 facets on girdle = 161
8-fold, mirror-image symmetry
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
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
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