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Nigerian Cushion gem design

Nigerian Cushion: 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 "Nigerian Cushion"

By Jeff R. Graham, updated on

Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)

Nigerian Cushion gem design

Nigerian Cushion (B12.JRG)
By Jeff R. Graham
Copyright 1999
87.2% Light Return
Angles for R.I. = 1.62
73 facets + 16 facets on girdle = 89
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.534 T/L = 0.534
P/W = 0.477 C/W = 0.179
H/W = (P+C)/W+0.02 = 0.676
P/H = 0.706 C/H = 0.265
Vol./W^3 = 0.263

Addition # 5 - I designed this for some of that large pink Tourmaline that has been coming out of Nigeria. It cuts easy and fairly fast for a Barion. This is best in light to medium color, clean materials. This works well in R.I. 1.62 to 1.76 (89.1%) with no changes. I use this as my default square cushion…


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Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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