Bygone: Faceting Design Diagram
Detailed information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Bygone".
Sunstone (Feldspar, Bytonite, Labradorite, Spectrolite, Orthoclase)
Bygone (SUN18.JRG)
By Jeff R. Graham
Copyright 2006
77.3% Light Return
Angles for R.I. = 1.54
55 facets + 6 facets on girdle = 61
6-fold, mirror-image symmetry
96 index
L/W = 1.155 T/W = 0.524 T/L = 0.454 P/W = 0.704
C/W = 0.194 H/W = (P+C)/W+0.02 = 0.918 P/H = 0.767 C/H = 0.211 Vol./W^3 = 0.411
PAVILION
CROWN
Addition # 11 - Cut in refractive indexes 1.54 to 2.14 with no changes. This is for light colored materials (no shiller) and it is killer in Beryl. This is pretty easy to cut. It may require a custom setting because of the depth. Note: The girdle can be cut in first and the P1 cut to meet so that center point is not needed and it saves rough.
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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.
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