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".


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.



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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