Double Dart: Faceting Design Diagram
Detailed information and guide on Faceting Designs. Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Double Dart".
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Double Dart (TLINE64.JRG)
By Jeff R. Graham
88% Light Return
Angles for R.I. = 1.62
121 facets + 8 facets on girdle = 129
8-fold, mirror-image symmetry
L/W = 1.000 T/W = 0.503 T/L = 0.503
P/W = 0.410 C/W = 0.202
H/W = (P+C)/W+0.02 = 0.632
P/H = 0.649 C/H = 0.319
Vol./W^3 = 0.207
Addition # 3 - This should be cut in a larger stone, the size of the P6,P7 are small and cut very fast. Some of these tiers have no meets, they have to be cut carefully. It can be hard to line up, medium material, 1-16cts. Cut in refractive indexes 1.62 to 1.93 (93%) with no changes.
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
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