Old Faithful: Faceting Design Diagram
Tips, details, and a guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Old Faithful".
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Old Faithful (TLINE59.JRG)
By Jeff R. Graham
Copyright 1998
84% Light Return
Angles for R.I. = 1.62
57 facets + 16 facets on girdle = 73
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.454 T/L = 0.454
P/W = 0.431 C/W = 0.185
H/W = (P+C)/W+0.02 = 0.636
P/H = 0.678 C/H = 0.291
Vol./W^3 = 0.207
Addition # 2 - This is still about one of the best cuts there is as far as I am concerned. Cut in refractive indexes 1.62 to 2.14 (92.2%) with no changes.
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
