Faceting Design Diagram: Hubcap – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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.

 

 


Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

About the author
Jeff R. Graham
The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.
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