Step’in Four: Faceting Design Diagram

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

Step'in Four (MIR81.JRG)
By Jeff R. Graham
Copyright 2005
87.4% Light Return
Angles for R.I. = 1.62
25 facets + 8 facets on girdle = 33
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.257 T/L = 0.257 P/W = 0.466
C/W = 0.182 H/W = (P+C)/W+0.02 = 0.668 P/H = 0.698 C/H = 0.272 Vol./W^3 = 0.252

PAVILION

CROWN

Addition # 10 - Cut in refractive indexes 1.62 to 1.76 with no changes. This works well in light to medium saturations. I use it for Garnets, particularly for earrings. It's pretty fast and easy to cut. The reflections will surprise you.

Detailed faceting instructions by Jeff Graham available at The Rock Peddler