Prop Square: 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 "Prop Square".
Topaz (Swiss, Electric, London Blue, Imperial, White, Yellow, Pink, Champange)
Prop Square (TOPAZ11.JRG)
By Jeff R. Graham
Copyright 1998
75.5% Light Return
Angles for R.I. = 1.62
53 facets + 4 facets on girdle = 57
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.589 T/L = 0.589
P/W = 0.550 C/W = 0.246
H/W = (P+C)/W+0.02 = 0.816
P/H = 0.674 C/H = 0.302
Vol./W^3 = 0.389
Addition # 2 - This is a nice cut, I like it in Tourmaline. The P6 facets are cut in until they look right, no meet. I like this pattern in a medium color material and around 2cts+. Cut in refractive indexes 1.62 to 1.93 (85.5%) with no changes.
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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