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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".

By Jeff R. Graham, updated on

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

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