Faceting Design Diagram: Diamond – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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

Diamond (B40.JRG)
By Jeff R. Graham
Copyright 2001
84.3% Light Return
Angles for R.I. = 1.62
61 facets + 8 facets on girdle = 69
2-fold, mirror-image symmetry
96 index
L/W = 1.175 T/W = 0.634 T/L = 0.540
P/W = 0.480 C/W = 0.192
H/W = (P+C)/W+0.02 = 0.692
P/H = 0.694 C/H = 0.277
Vol./W^3 = 0.272

Addition # 5 – Cut in R.I. 1.62 through 1.76 with no changes… This is fast to cut and makes an unusual stone. I like it in almost any material.


Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler