Cap: 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 "Cap".
Quartz (Amethyst, Citrine, Ametrine, Smokey, Rose)
Cap (B20.JRG)
By Jeff R. Graham
Copyright 2001
87.9% Light Return
Angles for R.I. = 1.54
67 facets + 16 facets on girdle = 83
2-fold, mirror-image symmetry
96 index
L/W = 1.342 T/W = 0.827 T/L = 0.616
P/W = 0.583 C/W = 0.202
H/W = (P+C)/W+0.02 = 0.806
P/H = 0.724 C/H = 0.251
Vol./W^3 = 0.439
Addition # 5 - Cut in R.I 1.54 to 1.76 (89.1%). This is harder to cut than it looks, be sure your L/W is correct. The table meets can be tough. This is designed for large Quartz, but works well in light man-made materials.
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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