In-Line Crown: Faceting Design Diagram


Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "In-Line Crown".

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Sapphire / Corundum (Ruby, Ceylon, Padparadschah, Pink, Yellow, Green)

In-Line Crown (CRUND1.JRG)
By Jeff R. Graham
Copyright 1993
79.3% Light Return
Angles for R.I. = 1.76
113 facets + 16 facets on girdle = 129
16-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.499 T/L = 0.499
P/W = 0.397 C/W = 0.206
H/W = (P+C)/W+0.02 = 0.623
P/H = 0.637 C/H = 0.331
Vol./W^3 = 0.214

Addition # 3 - This design works well with any Sapphire, in the light to medium dark range, 1/2-8cts. It has a lot of sparkle and is easy to cut. This is mainly for man-made material, but it will certainly work in real Sapphire if you are lucky and have a piece large enough. Cut in refractive indexes 1.73 to 2.14 (85.4%) 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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