Faceting Design Diagram: “Streeech” – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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

“Streeech” (TLINE24.JRG)
By Jeff R. Graham
Copyright 1998
72% Light Return
Angles for R.I. = 1.62
29 facets + 4 facets on girdle = 33
2-fold, mirror-image symmetry 96 index
L/W = 3.000 T/W = 2.394 T/L = 0.798
P/W = 0.557 C/W = 0.259
H/W = (P+C)/W+0.02 = 0.836
P/H = 0.666 C/H = 0.310
Vol./W^3 = 1.362

Addition # 3 – Cut a 3.0 L/W preform. I get tired of cutting steps in long Tourmaline crystals, so here is what I do. The crown can be cut as low as 32 (subtract 10 from each of the crown tiers). Open “c” is best, 1-18cts.


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.