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Flat Eye: 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 "Flat Eye".

By Jeff R. Graham, updated on

Spinel (Red, Pink, Lavender, Green, Blue, Orange, Violet)

Flat Eye (SPINEL8.JRG)
By Jeff R. Graham
Copyright 1998
76% Light Return
Angles for R.I. = 1.71
41 facets + 8 facets on girdle = 49
2-fold, mirror-image symmetry
96 index
L/W = 1.250 T/W = 0.814 T/L = 0.651
P/W = 0.393 C/W = 0.143
H/W = (P+C)/W+0.02 = 0.556
P/H = 0.707 C/H = 0.257
Vol./W^3 = 0.194

Addition # 2 - This is very nice and helps use up some of that flat rough that I always put off cutting. It works well in Garnet, CZ, Zircon, and Sapphire. It's light return is better than the ray trace says, 1/2-8cts.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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