“CC” Triangle: Faceting Design Diagram

Information and guide for Faceting Design Diagrams. This design is called a " "CC" Triangle". Roughing in the table before you cut the C5 is a good idea.


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

"CC" Triangle (AQUA6.JRG)
By Jeff R. Graham
Copyright 1995
70.8% Light Return
Angles for R.I. = 1.56
67 facets + 12 facets on girdle = 79
3-fold, mirror-image symmetry
96 index
L/W = 1.017 T/W = 0.633 T/L = 0.622
P/W = 0.439 C/W = 0.174
H/W = (P+C)/W+0.02 = 0.633
P/H = 0.693 C/H = 0.275
Vol./W^3 = 0.223

Gram Book 1 - Roughing in the table before you cut the C5 is a good idea. If you rough in the corners P4, C5(not final) it will help get a straight girdle. This is not easy to cut, you may have to adjust some angles, 1-12cts. Cut in refractive index 1.56 to 1.76 (79.8%) 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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