Old Faithful gem design
Old Faithful gem design

Old Faithful: Faceting Design Diagram


Tips, details, and a guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Old Faithful".

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Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)

Old Faithful gem design

Old Faithful (TLINE59.JRG)
By Jeff R. Graham
Copyright 1998
84% Light Return
Angles for R.I. = 1.62
57 facets + 16 facets on girdle = 73
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.454 T/L = 0.454
P/W = 0.431 C/W = 0.185
H/W = (P+C)/W+0.02 = 0.636
P/H = 0.678 C/H = 0.291
Vol./W^3 = 0.207

Addition # 2 - This is still about one of the best cuts there is as far as I am concerned. Cut in refractive indexes 1.62 to 2.14 (92.2%) 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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