Faceting Design Diagram: 12 Board – Quartz – Citrine, Amethyst, Ametrine, Smokey, Rose


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

12 Board (CHECK9.JRG)5.08 carat Amethyst
By Jeff R. Graham
Copyright 2001
89.1% Light Return
Angles for R.I. = 1.54
30 facets + 8 facets on girdle = 38
2-fold, mirror-image symmetry
96 index
L/W = 1.250 P/W = 0.450 C/W = 0.243
H/W = (P+C)/W+0.02 = 0.713
P/H = 0.631 C/H = 0.341 Vol./W^3 = 0.435

Addition # 6 – This is fast and bright, notice that there is no table. Cut the C4,C5 as evenly as you can, there is no real meet point on them. I like this in about any material.


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.