Royal Mine: Faceting Design Diagram
Detailed information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Royal Mine".
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Royal Mine (CHECK63.JRG)
By Jeff R. Graham
Copyright 2003
87.4% Light Return
Angles for R.I. = 1.62
61 facets + 8 facets on girdle = 69
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.372
T/L = 0.372 P/W = 0.441 C/W = 0.182
H/W = (P+C)/W+0.02 = 0.643
P/H = 0.686 C/H = 0.282
Vol./W^3 = 0.234
Addition # 8 - This one is really neat. I have always liked an antique/mine cut and this one with a diamond top is cool. Cut in refractive indexes 1.62 to 2.14 (89.7%) with no changes. This works in about any material.
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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