Faceting Design Diagram: Hor-I-zon Sun – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite

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

Hor-I-zon Sun (MC29.JRG)
By Jeff R. Graham
Copyright 1998
89.8% Light Return
Angles for R.I. = 1.62
61 facets + 19 facets on girdle = 80
1-fold, mirror-image symmetry
96 index
L/W = 1.012 T/W = 0.528 T/L = 0.521
P/W = 0.410 C/W = 0.159
H/W = (P+C)/W+0.02 = 0.589
P/H = 0.696 C/H = 0.271
Vol./W^3 = 0.171

Addition # 4 – This is a neat one to try for a change of pace. It is not really hard to cut and because it is based on a round it has very good light return. The reflection looks like rays, cut in a larger size 2cts+. This works in Topaz and Peridot. Cut this in R.I. 1.62 to 1.76 without changes.

Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

Gram Faceting Archive of Information
This edited version of an article by the late Jeff Graham is part of a special archived informational series from Gram Faceting. Used with permission.