Beryl (Aquamarine, Emerald, Helidore, Bixbite, Goshenite, Morganite, Golden Beryl)
Pinch (AQUA7.JRG)
By Jeff R. Graham
Copyright 1995
70.8% Light Return
Angles for R.I. = 1.56
71 facets + 8 facets on girdle = 79
2-fold, mirror-image symmetry
96 index
L/W = 1.503 T/W = 0.956 T/L = 0.636
P/W = 0.500 C/W = 0.197
H/W = (P+C)/W+0.02 = 0.717
P/H = 0.697 C/H = 0.275
Vol./W^3 = 0.438
Gram Book 1 – This is a good design for some of those long Beryl crystals. A preform helps, be sure that the 1.50 L/W is right. This design gives nice color and return on crystal shaped rough. This is not easy to cut, 1-12cts. Cut in refractive index 1.56 to 1.76 (75%) with no changes.
Random – Cosine – ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
This edited version of an article by the late Jeff Graham is part of a special archived informational series from Gram Faceting. Used with permission.
