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


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

Brilliant Square (MIR37.JRG)
By Jeff R. Graham
Copyright 2004
91.6% 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 = 0.325 T/L = 0.325
P/W = 0.466 C/W = 0.189
H/W = (P+C)/W+0.02 = 0.675
P/H = 0.691 C/H = 0.279
Vol./W^3 = 0.272

Addition # 9 – Cut in refractive indexes 1.62 to 2.14 with no changes. This is fast and not hard to cut. Note: The C4 tier cuts to the corners at 96-24- 48-72, the facets do not point, just cut them evenly. This is great in about any material and I like it in all 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.