Penta Brilliant: 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 "Penta Brilliant".0
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Penta Brilliant (MC82.JRG)
By Jeff R. Graham
86.5% Light Return
Angles for R.I. = 1.62
86 facets + 5 facets on girdle = 91
5-fold, mirror-image symmetry
L/W = 1.051 T/W = 0.369 T/L = 0.351
P/W = 0.470 C/W = 0.284
H/W = (P+C)/W+0.02 = 0.774
P/H = 0.607 C/H = 0.367
Vol./W^3 = 0.274
Addition # 7 - This is great in light to medium colored Quartz with no changes. Cut this in refractive indexes 1.54 to 2.14 with no changes. This is really nice in light Beryl. C2 on the crown is just cut to center point like P1 is.
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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