Faceting Design Diagram: Crown Star – Tourmaline – Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite


Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)

Crown Star (CHECK14.JRG)Chrysoberyl cut by Tony Carson
By Jeff R. Graham
Copyright 2001
88% Light Return
Angles for R.I. = 1.62
53 facets + 12 facets on girdle = 65
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.373 T/L = 0.373
P/W = 0.442 C/W = 0.180
H/W = (P+C)/W+0.02 = 0.642
P/H = 0.688 C/H = 0.281
Vol./W^3 = 0.259

Addition # 6 – Cut this in refractive indexes 1.62 to 1.92 with no changes. This makes a very bright and sparkly stone. Notice that the pavilion facets P5, P6 are creating a lot of movement.


Random – Cosine – ISO

 

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

About the author
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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