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“U” Rect: Faceting Design Diagram


Details and information on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts and facets suitable for different gems.

By Jeff R. Graham, updated on

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

"U" Rect (TLINE48.JRG)
By Jeff R. Graham
Copyright 1998
82.3% Light Return
Angles for R.I. = 1.62
47 facets + 6 facets on girdle = 53
2-fold, mirror-image symmetry
96 index
L/W = 1.330 T/W = 0.758 T/L = 0.570
P/W = 0.451 C/W = 0.166
H/W = (P+C)/W+0.02 = 0.636
P/H = 0.708 C/H = 0.260
Vol./W^3 = 0.310

Addition # 3 - The 39 degree tier on the Pavilion are below the critical angle for 1.54, but because of the L/W on this cut it works in Quartzs also. This is a good cut for about any material and is not very hard, 1-12cts.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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