
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".
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
Related Articles
Opal Stones and Gems: Value, Price, and Jewelry Information
Opal Symbolism
Product Review, Opal The Smart Chart
Australian Opals
Latest Articles
Milarite Value, Price, and Jewelry Information
Appraising Pearls: How to Grade Pearls
Agate Buying Guide
Carving Techniques for Handling Inclusions in Transparent Gems
Never Stop Learning
When you join the IGS community, you get trusted diamond & gemstone information when you need it.