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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".

By Jeff R. Graham, updated on

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

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