Flat Top Opal: Faceting Design Diagram
Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Flat Top Opal".
Opal (Jelly, Cherry, Orange, Clear)
Flat Top Opal (OPAL1.JRG)
By Jeff R. Graham
Copyright 1998
82% Light Return
Angles for R.I. = 1.45
89 facets + 16 facets on girdle = 105
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.513 T/L = 0.513
P/W = 0.479 C/W = 0.171
H/W = (P+C)/W+0.02 = 0.669
P/H = 0.715 C/H = 0.255
Vol./W^3 = 0.251
Addition # 2 - Opal is hard to get any flash out of. The crown is pretty flat to help improve light return. Any good color 2-12cts. Cut in refractive indexes 1.45 to 1.93 (88.2%) with no changes. This design will work well in Moldavite.
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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