Flat Top Opal: Faceting Design Diagram

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