Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Diamond Eye 1.50 (CHECK82.JRG)
By Jeff R. Graham
Copyright 2003
76.5% Light Return
Angles for R.I. = 1.62
35 facets + 12 facets on girdle = 47
2-fold, mirror-image symmetry
96 index
L/W = 1.502
T/W = 0.421
T/L = 0.280 P/W = 0.430 C/W = 0.232
H/W = (P+C)/W+0.02 = 0.682
P/H = 0.631
C/H = 0.340
Vol./W^3 = 0.264
Addition # 8 – This is brighter than the ray trace may lead you to think and works well in about any material. There are not very many 1.50 marquises around that are worth cutting and it cuts fast and is nice. It is very pretty in pink Tourmaline.
Random – Cosine – ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler