Glow: 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 "Glow-Tourmaline".
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Glow (MIR27.JRG)
By Jeff R. Graham
Copyright 2004
91.5% Light Return
Angles for R.I. = 1.62
46 facets + 5 facets on girdle = 51
5-fold, mirror-image symmetry
80 index
L/W = 1.051 T/W = 0.172 T/L = 0.164
P/W = 0.382 C/W = 0.246
H/W = (P+C)/W+0.02 = 0.648
P/H = 0.589 C/H = 0.380
Vol./W^3 = 0.196
Addition # 9 - This is designed for lightly saturated materials like Tourmaline and Aquamarine. Try this in a light Tourmaline nodule, it is a real sparkler. Cut in refractive indexes 1.54 to 2.14 with no changes. The table can be skipped on a small stone.
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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