3.0 Butterfly: Faceting Design Diagram
Detailed information and guide on Faceting Designs. Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "3.0 Butterfly"
Beryl (Aquamarine, Emerald, Helidore, Bixbite, Goshenite, Morganite, Golden Beryl)
3.0 Butterfly (MC11.JRG)
By Jeff R. Graham
Copyright 1999
89.5% Light Return
Angles for R.I. = 1.56
21 facets + 4 facets on girdle = 25
2-fold, mirror-image symmetry
96 index
L/W = 3.000 T/W = 2.478 T/L = 0.826
P/W = 0.645 C/W = 0.163
H/W = (P+C)/W+0.02 = 0.828
P/H = 0.779 C/H = 0.197
Vol./W^3 = 1.427
Addition # 4 - This is easy to cut, but care must be taken not to chip the long sharp keel. I use this design for long Beryl crystals, it works best if they have decent color to them. Can be cut in a different order if you want, 1cts+. This also works well in Tourmaline. Cut this in R.I. 1.56 to 1.93 without changes.
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
