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".0
Opal (Jelly, Cherry, Orange, Clear)
Flat Top Opal (OPAL1.JRG)
By Jeff R. Graham
82% Light Return
Angles for R.I. = 1.45
89 facets + 16 facets on girdle = 105
8-fold, mirror-image symmetry
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
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