Faceting Design Diagram: Swirl Dutch – Tourmaline, Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


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

Swirl Ducth Jeff Graham Facet Design 1 Swirl Ducth Jeff Graham Facet Design 2

Swirl Dutch (DOME17.JRG)
By Jeff R. Graham
Copyright 2007
84.8% Light Return
Angles for R.I. = 1.62
129 facets + 16 facets on girdle = 145
16-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.322 T/L = 0.322 P/W = 0.405 C/W = 0.336
H/W = (P+C)/W+0.02 = 0.761 P/H = 0.532 C/H = 0.441
Vol./W^3 = 0.259

Addition # 13 – Cut in refractive indexes 1.62 to 1.76 with no changes. This is for lightly saturated materials and is fun to cut. It a unique look. It is not hard to cut, other than it has a lot of facets.

Swirl Ducth Jeff Graham Facet Design 3

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.