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12 Board: Faceting Design Diagram


Details and information on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts and facets suitable for different gems.

By Jeff R. Graham, updated on

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

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