Tang: Faceting Design Diagram

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

Tang (MIR39.JRG)
By Jeff R. Graham
Copyright 2004
91.5% Light Return
Angles for R.I. = 1.62
31 facets + 9 facets on girdle = 40
3-fold, mirror-image symmetry
96 index
L/W = 1.038 T/W = 0.407 T/L = 0.393
P/W = 0.412 C/W = 0.200
H/W = (P+C)/W+0.02 = 0.632
P/H = 0.652 C/H = 0.317
Vol./W^3 = 0.201

Addition # 9 - This is very bright and is ideal for light to medium saturated materials. It yields great for "c" axis Tourmaline. Cut in refractive indexes 1.62 to 1.76 with no changes. This is fast to cut and looks great. Hint: The P5 can be cut at a little lower angle and makes interesting reflections.

Random - Cosine - ISO

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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