Sp Dirk: Faceting Design Diagram

Successful tips, details and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Sp Dirk"


Zircon (Hyacinth, Starlite)

Sp Dirk (MC58.JRG)
By Jeff R. Graham
Copyright 2002
79.6% Light Return
Angles for R.I. = 1.93
31 facets + 6 facets on girdle = 37
3-fold, mirror-image symmetry
96 index
L/W = 1.155 T/W = 0.481 T/L = 0.417
P/W = 0.518 C/W = 0.169
H/W = (P+C)/W+0.02 = 0.706
P/H = 0.733 C/H = 0.239
Vol./W^3 = 0.221

Addition # 7 - Cut in refractive indexes 1.76 to 2.20 with no changes. This is designed for light material with a high refractive index like Zircon. There are not a lot of facets on this design, but the sparkle is quite good. This design is good for accent stones that are on the small side, although it also works well in a large stone.


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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