Long Diamond: Faceting Design Diagram
Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Long Diamond".
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Long Diamond (CHECK67.JRG)
By Jeff R. Graham
84.5% Light Return
Angles for R.I. = 1.62
27 facets + 4 facets on girdle = 31
2-fold, mirror-image symmetry
L/W = 2.001 T/W = 0.967 T/L = 0.483
P/W = 0.420 C/W = 0.300
H/W = (P+C)/W+0.02 = 0.740
P/H = 0.567 C/H = 0.405
Vol./W^3 = 0.896
Addition # 8 - This is a good design for about any Tourmaline, it's a nice change from a regular rectangle. This works best in 1.62 but can be cut in refractive index up to 2.14 with no changes.
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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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