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1.40 Roval: 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

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

1.40 Roval (MC37.JRG)3.60 carat Zircon
By Jeff R. Graham
Copyright 1999
88.1% Light Return
Angles for R.I. = 1.62
49 facets + 10 facets on girdle = 59
2-fold, mirror-image symmetry
96 index
L/W = 1.414 T/W = 0.947 T/L = 0.670
P/W = 0.615 C/W = 0.160
H/W = (P+C)/W+0.02 = 0.795
P/H = 0.773 C/H = 0.202
Vol./W^3 = 0.478

Addition # 4 - I usually rough in the P4(G) after I cut the P2(G) to get an idea of where the P3's cut to. It can be done either way with no problem. This works well in about any material, 1cts+. Cut this in R.I. 1.62 to 1.76 without changes.

 

 


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Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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