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Tourmaline 20: Faceting Design Diagram


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

By Jeff R. Graham, updated on

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

Tourmaline 20 (MC32.JRG) 1.87 carat Tourmaline
By Jeff R. Graham
Copyright 1998
83.6% Light Return
Angles for R.I. = 1.62
43 facets + 8 facets on girdle = 51
2-fold, mirror-image symmetry
96 index
L/W = 2.000 T/W = 1.354 T/L = 0.677
P/W = 0.493 C/W = 0.181
H/W = (P+C)/W+0.02 = 0.694
P/H = 0.710 C/H = 0.261
Vol./W^3 = 0.744

Addition # 4 - If you are cutting in Tourmaline, be sure that the "c" axis is close in color to the a/b or this design will get muddy. The keel on this is harder than it looks, it works well in Topaz, 1-12cts. Cut this in R.I. 1.62 to 1.76 (82.4%) without changes.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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