Big “M”: 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 "Big "M" ".
Big "M" (B10.JRG)
By Jeff R. Graham
83.4% Light Return
Angles for R.I. = 1.54
73 facets + 16 facets on girdle = 89
2-fold, mirror-image symmetry
L/W = 1.508 T/W = 0.795 T/L = 0.527P/W = 0.657 C/W = 0.197
H/W = (P+C)/W+0.02 = 0.874P/H = 0.752 C/H = 0.225
Vol./W^3 = 0.457
Addition # 5 - Notice the break angles are steep on the long side of the stone. They could cause some problems in setting if there are prongs there. If set from the tips it should be no problem. This will window somewhat in a low R.I. because of the L/W.. It will work in R.I. 1.54 to 1.93 (88.6%) with no changes.
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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