Faceting Design Diagram: Contort – Feldspar – Bytonite, Labradorite, Spectrolite, Orthoclase


Sunstone (Feldspar, Bytonite, Labradorite, Spectrolite, Orthoclase)

Contort Jeff Graham Facet Design

Contort Jeff Graham Facet Design

Contort (SUN42.JRG)
By Jeff R. Graham
Copyright 2006
81.8% Light Return
Angles for R.I. = 1.54
27 facets + 6 facets on girdle = 33
2-fold, mirror-image symmetry
96 index
L/W = 2.012 T/W = 0.576 T/L = 0.287 P/W = 0.456
C/W = 0.242 H/W = (P+C)/W+0.02 = 0.718 P/H = 0.635 C/H = 0.337 Vol./W^3 = 0.566

Addition # 11 – Cut in refractive indexes 1.54 to 2.14 with no changes. Note: Cut the L/W and then just cut the P3(G) until they point. This works well in colored material and watermelon. The points can be fragile so care must be taken.

Contort Jeff Graham Facet Design

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.