Spike: Faceting Design Diagram
Details, tips, and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Spike -Tourmaline"0
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
By Jeff R. Graham
82.8% Light Return
Angles for R.I. = 1.62
61 facets + 10 facets on girdle = 71
5-fold, mirror-image symmetry
L/W = 1.025 T/W = 0.190 T/L = 0.185 P/W = 0.404 C/W = 0.350
H/W = (P+C)/W+0.02 = 0.774 P/H = 0.523 C/H = 0.452
Vol./W^3 = 0.269
Addition # 13 - Cut in refractive indexes 1.62 to 2.14 with no changes. This is interesting and works well in light to medium saturated material. It is not difficult to cut and I like it in Peridot or Tourmaline.
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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