Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)

Triple Star (TLINE14.JRG)
By Jeff R. Graham
Copyright 1993
78.5% Light Return
Angles for R.I. = 1.62
113 facets + 16 facets on girdle = 129
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.535 T/L = 0.535
P/W = 0.423 C/W = 0.185
H/W = (P+C)/W+0.02 = 0.628
P/H = 0.673 C/H = 0.295
Vol./W^3 = 0.221

Gram Book 1 – This design is good for a large stone 1-20cts, in light to medium material. It is not hard to cut, and it has a lot of sparkle. The star in the point of the Pavilion makes the table lively. Cut in refractive index 1.62 to 2.14 (89.5%) with no changes.

 


Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler