77 Turbo: 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 "77 Turbo"
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
77 Turbo (MIR34.JRG)
By Jeff R. Graham
Copyright 2004
93.9% Light Return
Angles for R.I. = 1.62
71 facets + 7 facets on girdle = 78
7-fold, mirror-image symmetry
77 index
L/W = 1.026 T/W = 0.389 T/L = 0.379
P/W = 0.417 C/W = 0.162
H/W = (P+C)/W+0.02 = 0.599
P/H = 0.697 C/H = 0.270
Vol./W^3 = 0.195
Addition # 9 - Cut in refractive indexes 1.62 to 2.14 with no changes. This is bright with a lot of sparkle. It looks like it has thousands of facets. Light to medium saturated stones works well although it is quite nice in a quality Garnet.
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
