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
Copyright 1998
88% Light Return
Angles for R.I. = 1.62
121 facets + 8 facets on girdle = 129
8-fold, mirror-image symmetry
96 index
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

Jeff R. Graham

The late Jeff Graham was a prolific faceter, creator of many original faceting designs, and the author of several highly-regarded instructional faceting books such as Gram Faceting Designs.

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