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

Plus Six (CHECK2.JRG)
By Jeff R. Graham
Copyright 2001
90.2 % Light Return
Angles for R.I. = 1.62
23 facets + 6 facets on girdle = 29
6-fold, mirror-image symmetry
96 index
L/W = 1.155 T/W = 0.280 T/L = 0.243
P/W = 0.405 C/W = 0.181
H/W = (P+C)/W+0.02 = 0.606
P/H = 0.668 C/H = 0.299
Vol./W^3 = 0.232

Addition # 6 - This was designed for a rather large piece of Nigerian Tourmaline that I wanted to cut. The stone was six-sided with Rubellite outside with a peach center. I wanted something that would be bright and show off the unusual quality of the rough. I prefer checkerboards for material that is saturated and here is what I came up with. This works well in Garnet, darker Sapphire and most man-made materials.

 

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