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Twinkle: 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 "Twinkle"

By Jeff R. Graham, updated on

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

Twinkle (MIR40.JRG)
By Jeff R. Graham
Copyright 2004
86% Light Return
Angles for R.I. = 1.62
40 facets + 6 facets on girdle = 46
3-fold, mirror-image symmetry
96 index
L/W = 1.155 T/W = 0.385 T/L = 0.334
P/W = 0.397 C/W = 0.212
H/W = (P+C)/W+0.02 = 0.630
P/H = 0.631 C/H = 0.337
Vol./W^3 = 0.239

Addition # 9 - This is not hard to cut, but the meets can be a little tough from a technical standpoint. This works well in any material. Cut in refractive indexes 1.62 to 1.76 with no changes. This is nice in Garnet.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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