Gram Barion Pear: 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 "Gram Barion Pear"
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Gram Barion Pear (B42.JRG)
By Jeff R. Graham
Copyright 2001
86.2% Light Return
Angles for R.I. = 1.62
74 facets + 16 facets on girdle = 90
1-fold, mirror-image symmetry
96 index
L/W = 1.436 T/W = 0.677 T/L = 0.472
P/W = 0.624 C/W = 0.185
H/W = (P+C)/W+0.02 = 0.829
P/H = 0.753 C/H = 0.223
Vol./W^3 = 0.432
Addition # 5 - A lot of people have asked me for a Barion pear that performs well. Here it is… Cut in R.I. 1.62 to 1.93 (87.0%) with no changes. I recommend large and light materials for this design. The breaks are steep, set it from the ends. Notice the P21 & P22 do not meet breaks, these absorb any slack in case your L/W is off a bit. P22 can be fudged to meet breaks… I fudge.
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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