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Shadow Star: Faceting Design Diagram


Helpful tips, details and guide on Faceting Designs. Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Shadow Star".

By Jeff R. Graham, updated on

Opal (Jelly, Cherry, Orange, Clear)

Shadow Star (OPAL4.JRG)
By Jeff R. Graham
Copyright 1993
63% Light Return
Angles for R.I. = 1.45
36 facets + 5 facets on girdle = 41
5-fold, mirror-image symmetry
80 index
L/W = 1.051 T/W = 0.553 T/L = 0.526
P/W = 0.509 C/W = 0.224
H/W = (P+C)/W+0.02 = 0.753
P/H = 0.676 C/H = 0.297
Vol./W^3 = 0.281

Addition # 3 - Cutting a preform will save rough. Yes, the P4 facets are below the critical angle (C.A.) that's why I frost them and sometimes the P1's too. It gives the stone a nice star effect. The P4 can be left off too, if you want. This will work in Moldivite… Cut in refractive indexes 1.45 to 2.14 (72%) with no changes.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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