Light Star: Faceting Design Diagram
Detailed information and guide for Faceting Design Diagrams. This facet design is called a "Light Star". It has a nice light return, higher than the 63%.
Quartz (Amethyst, Citrine, Ametrine, Smokey, Rose)
Light Star (QTZ18.JRG)
By Jeff R. Graham
Copyright 1993
63.5% Light Return
Angles for R.I. = 1.54
169 facets + 16 facets on girdle = 185
8-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.472 T/L = 0.472
P/W = 0.449 C/W = 0.192
H/W = (P+C)/W+0.02 = 0.661
P/H = 0.679 C/H = 0.291
Vol./W^3 = 0.226
Addition # 1 - This design has a nice light return, higher than the 63%. Light lost is around the girdle C1 facets, because of the depth of the stone. Cut in refractive indexes with no changes 1.54 to 1.93 (87.7%) and in a larger sized stone.
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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