Faceting Design Diagram: Big “M” – Quartz – Citrine, Amethyst, Ametrine, Smokey, Rose


Quartz (Amethyst, Citrine, Ametrine, Smokey, Rose)

13.94 carat Amethyst

Big “M” (B10.JRG)
By Jeff R. Graham
Copyright 1999
83.4% Light Return
Angles for R.I. = 1.54
73 facets + 16 facets on girdle = 89
2-fold, mirror-image symmetry
96 index
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