“DC” Mark: Faceting Design Diagram

Information and guide for Faceting Design Diagrams. This facet design is called a " "DC" Mark". This stone has almost no light lost through the bottom.


Topaz (Swiss, Electric, London Blue, Imperial, White, Yellow, Pink, Champange)

"DC" Mark (TOPAZ14.JRG)
By Jeff R. Graham
Copyright 1998
75.5% Light Return
Angles for R.I. = 1.62
67 facets + 12 facets on girdle = 79
2-fold, mirror-image symmetry
96 index
L/W = 1.500 T/W = 0.731 T/L = 0.487
P/W = 0.434 C/W = 0.240
H/W = (P+C)/W+0.02 = 0.694
P/H = 0.625 C/H = 0.346
Vol./W^3 = 0.338

Addition # 3 - This stone has almost no light lost through the bottom. It is deep for lighter material, and has great sparkle. This is a non standard L/W and might take a custom head It cuts well in any medium light material, 1- 12cts.

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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