Square Barb: Faceting Design Diagram


Detailed information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Square Bob".

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Garnet (Pyrope, Rhodolite, Almandine, Spessartite, Grossular, Demantoid, Tsavorite)

Square Barb (GNETP35.JRG)
By Jeff R. Graham
Copyright 1997
92.5% Light Return
Angles for R.I. = 1.73
57 facets + 8 facets on girdle = 65
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.390 T/L = 0.390
P/W = 0.410 C/W = 0.158
H/W = (P+C)/W+0.02 = 0.588
P/H = 0.697 C/H = 0.269
Vol./W^3 = 0.231

Addition # 3 - A nice cut for most Garnet, it's not very hard, but watch the C6. On a smaller stone it will have to be hand cut, or left out. Cut in size 1-8cts. Cut in refractive indexes 1.73 to 2.14 (92.1%) 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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