Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Tack – Reflector (CHECK3.JRG)
By Jeff R. Graham
Copyright 2000
88.9% Light Return
Angles for R.I. = 1.62
37 facets + 8 facets on girdle = 45
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.235 T/L = 0.235
P/W = 0.478 C/W = 0.206
H/W = (P+C)/W+0.02 = 0.704
P/H = 0.679 C/H = 0.293
Vol./W^3 = 0.300
Addition # 6 – This is a neat one, the flashes are a true check. Notice that the corners float, this is to help get yield if your rough is not just right. Cut the corners in as close as you can to the diagram. If you are a bit off it will not really change much. I designed this for a piece of light multi-colored Tourmaline.
Random – Cosine – ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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