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Tang: Faceting Design Diagram


Successful tips, details and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Tang".

By Jeff R. Graham, updated on

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

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