8-12 Star: Faceting Design Diagram
Detailed information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "8-12 Star"0
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
8-12 Star (TLINE21.JRG)
By Jeff R. Graham
70.3% Light Return
Angles for R.I. = 1.62
77 facets + 8 facets on girdle = 85
4-fold, mirror-image symmetry
L/W = 1.000 T/W = 0.454 T/L = 0.454
P/W = 0.493 C/W = 0.224
H/W = (P+C)/W+0.02 = 0.737
P/H = 0.669 C/H = 0.304
Vol./W^3 = 0.276
Addition # 1 - The P1,P2(G),P3 facets can be cut in another order if you want. It could be cut P2(G),P3,P1, use whatever works for you, light to medium material 1-12cts. Cut in refractive indexes 1.62 to 1.93 (89.1%) with no changes. Notice that this is a deep design and it will work well in light colored materials.
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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