Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Pearl (CHECK33.JRG) 
By Jeff R. Graham
Copyright 2001
88.3% Light Return
Angles for R.I. = 1.62
53 facets + 17 facets on girdle = 70
1-fold, mirror-image symmetry
96 index
L/W = 1.165 T/W = 0.199 T/L = 0.171
P/W = 0.435 C/W = 0.217
H/W = (P+C)/W+0.02 = 0.672
P/H = 0.647 C/H = 0.324
Vol./W^3 = 0.241
Addition # 6 – I designed this to go with pearls. I wanted something roundish, but not quite round. I originally had Tourmaline in mind, but this works well for stones in refractive indexes 1.73 to 1.93 with no changes.
Random – Cosine – ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
IGS Become Member
