
Bi-Color Split: Faceting Design Diagram
An informational guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Bi-Color Split".
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)

Bi-Color Split (TLINE66.JRG)
By Jeff R. Graham
Copyright 1998
83% Light Return
Angles for R.I. = 1.62
33 facets + 8 facets on girdle = 41
2-fold, mirror-image symmetry
96 index
L/W = 2.000 T/W = 1.446 T/L = 0.723
P/W = 0.536 C/W = 0.236
H/W = (P+C)/W+0.02 = 0.793
P/H = 0.677 C/H = 0.298
Vol./W^3 = 0.855
Addition # 3 - Thanks to a friend of mine named Paul I got this idea from him (with his permission) and put my own spin on it. This design is for bi-colored Tourmaline, it flashes from the middle to the edge depending on how it's rocked, 1-24cts.
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Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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