Faceting Design Diagram: Bygone Era – Feldspar – Bytonite, Labradorite, Spectrolite, Orthoclase


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

Bygone Era Jeff Graham Facet Design

Bygone Era Jeff Graham Facet Design

Bygone Era (SUN26.JRG)
By Jeff R. Graham
Copyright 2006
80.6%Light Return
Angles for R.I. = 1.54
57 facets + 8 facets on girdle = 65
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.489 T/L = 0.489 P/W = 0.697
C/W = 0.206 H/W = (P+C)/W+0.02 = 0.923 P/H = 0.755 C/H = 0.223 Vol./W^3 = 0.391

Addition # 11 – Cut in refractive indexes 1.54 to 2.14 with no changes. This is designed for light colored rough, and is very good in Aquamarine. This is fairly fast and easy to cut. This can be cut to the girdle instead of center point to save rough.

Bygone Era Jeff Graham Facet Design

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

About the author
Jeff R. Graham
The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.
All articles by this author