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

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

Play Ball (CHECK77.JRG)
By Jeff R. Graham
Copyright 2003
85.8% Light Return
Angles for R.I. = 1.62
57 facets + 8 facets on girdle = 65
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.350 T/L = 0.350
P/W = 0.431 C/W = 0.167
H/W = (P+C)/W+0.02 = 0.618
P/H = 0.698 C/H = 0.270
Vol./W^3 = 0.217

Addition # 8 – Cut this in refractive indexes 1.62 to 2.14 (90.2%) with no changes. This is pretty quick to cut and works well in about any material. I like it in medium colors.


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.