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".

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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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