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


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

Tabby (B8.JRG)
By Jeff R. Graham
Copyright 1999
78.4% Light Return
Angles for R.I. = 1.54
79 facets + 18 facets on girdle = 97
3-fold, mirror-image symmetry
96 index
L/W = 1.005 T/W = 0.591 T/L = 0.588
P/W = 0.515 C/W = 0.139
H/W = (P+C)/W+0.02 = 0.674
P/H = 0.765 C/H = 0.206
Vol./W^3 = 0.238

Addition # 5 – This cuts nicly in a large Quartz or Topaz. Cut P1 to center point, then cut the girdle to meet, then cut in the breaks. The light ray trace is misleading, it is really a bright stone, especially in light material. This is 91.2% in R.I. 1.62 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.