Opposed Bar 1.50: Faceting Design Diagram
Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Opposed Bar 1.50"
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Opposed Bar 1.50 (MC22.JRG)
By Jeff R. Graham
Copyright 1999
88.4% Light Return
Angles for R.I. = 1.62
17 facets + 8 facets on girdle = 25
2-fold, mirror-image symmetry
96 index
L/W = 1.500 T/W = 0.862 T/L = 0.575
P/W = 0.482 C/W = 0.212
H/W = (P+C)/W+0.02 = 0.714
P/H = 0.675 C/H = 0.297
Vol./W^3 = 0.634
Addition # 4 - This cut easy and can be almost any L/W with no changes. It works well in Tourmaline that is dark or closed on the "c" axis. You can cut the corners in or leave them pointed, 1cts and up… NOTE: P5 is optional. Cut this in R.I. 1.62 to 1.76 without changes.
Random - Cosine - ISO
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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