Faceting Design Diagram: Equal – Beryl – Aquamarine, Emerald, Helidore, Bixbite, Goshenite, Morganite, Golden Beryl


Beryl (Aquamarine, Emerald, Helidore, Bixbite, Goshenite, Morganite, Golden Beryl)

Equal (B38.JRG)
By Jeff R. Graham
Copyright 2001
82.2% Light Return
Angles for R.I. = 1.56
49 facets + 9 facets on girdle = 58
3-fold, mirror-image symmetry
96 index
L/W = 1.010 T/W = 0.500 T/L = 0.495
P/W = 0.508 C/W = 0.169
H/W = (P+C)/W+0.02 = 0.697
P/H = 0.729 C/H = 0.242
Vol./W^3 = 0.260

Addition # 5 – This can be cut with no changes in 1.56 to 1.93 and the performance is almost identical. This cuts fast and easy. It’s a good design for a new cutter.


Random – Cosine – ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

Gram Faceting Archive of Information
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.