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Hubcap: 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 "Hubcap".

By Jeff R. Graham, updated on

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

Hubcap (TLINE25.JRG)
By Jeff R. Graham
Copyright 1995
75% Light Return
Angles for R.I. = 1.62
105 facets + 8 facets on girdle = 113
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.497 T/L = 0.497
P/W = 0.441 C/W = 0.176
H/W = (P+C)/W+0.02 = 0.637
P/H = 0.692 C/H = 0.276
Vol./W^3 = 0.205

Gram Book 1 - The table is about 50% and it helps a lot if you rough it in before cutting the C4 facets, because they meet. This design is nice in about any color, 1-8cts. The reflection is higher than the ray trace indicates. Cut in refractive index 1.62 to 2.14 (85.3%) with no changes.

 

 


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Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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