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
86.2% Light Return
Angles for R.I. = 1.62
74 facets + 16 facets on girdle = 90
1-fold, mirror-image symmetry
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
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