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Pinch: Faceting Design Diagram


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

By Jeff R. Graham, updated on

Beryl (Aquamarine, Emerald, Helidore, Bixbite, Goshenite, Morganite, Golden Beryl)

Pinch (AQUA7.JRG)
By Jeff R. Graham
Copyright 1995
70.8% Light Return
Angles for R.I. = 1.56
71 facets + 8 facets on girdle = 79
2-fold, mirror-image symmetry
96 index
L/W = 1.503 T/W = 0.956 T/L = 0.636
P/W = 0.500 C/W = 0.197
H/W = (P+C)/W+0.02 = 0.717
P/H = 0.697 C/H = 0.275
Vol./W^3 = 0.438

Gram Book 1 - This is a good design for some of those long Beryl crystals. A preform helps, be sure that the 1.50 L/W is right. This design gives nice color and return on crystal shaped rough. This is not easy to cut, 1-12cts. Cut in refractive index 1.56 to 1.76 (75%) with no changes.

 

 


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Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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