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“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.

By Jeff R. Graham, updated on

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

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