Faceting Design Diagram: Four Square Sapphire – Sapphire / Corundum – Ruby, Ceylon, Padparadschah, Pink, Yellow, Green


Sapphire / Corundum (Ruby, Ceylon, Padparadschah, Pink, Yellow, Green)

Four Square Sapphire (SAP.JRG)
By Jeff R. Graham
Copyright 1994
85.9% Light Return
Angles for R.I. = 1.76
45 facets + 8 facets on girdle = 53
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.493 T/L = 0.493
P/W = 0.438 C/W = 0.206
H/W = (P+C)/W+0.02 = 0.665
P/H = 0.659 C/H = 0.311
Vol./W^3 = 0.241

Gram Book 1 – Here is a nice design, it cuts fast and is good in about any size or color. The top is a little different to cut, so pay attention, it is not hard. 1/2-6cts. Cut in refractive index 1.76 to 1.93 (86.5%) with no changes.


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.