Glass Triangle: Faceting Design Diagram

Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Glass Triangle".


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

Glass Triangle (QTZ22.JRG)
By Jeff R. Graham
Copyright 1993
80% Light Return
Angles for R.I. = 1.54
67 facets + 12 facets on girdle = 79
3-fold, mirror-image symmetry
96 index
L/W = 1.003 T/W = 0.433 T/L = 0.432
P/W = 0.447 C/W = 0.198
H/W = (P+C)/W+0.02 = 0.666
P/H = 0.672 C/H = 0.298
Vol./W^3 = 0.202

Gram Book 1 - This triangle is medium to hard to cut, it has a lot of meet points. The Pavilion has a lot of long narrow facets at different angles, which gives the stone a lot of sparkle. Light to med material, 1-16cts. A larger stone is easier to cut. This works well in Tourmaline and Topaz.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

Jeff R. Graham

The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.

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