Asterism Revisited: Faceting Design Diagram
Information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Asterism Revisited".
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Asterism Revisited (DOME10.JRG)
By Jeff R. Graham
Copyright 2007
87.7% Light Return
Angles for R.I. = 1.62
145 facets + 12 facets on girdle = 157
12-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.309 T/L = 0.309 P/W = 0.405
C/W = 0.336 H/W = (P+C)/W+0.02 = 0.761 P/H = 0.532 C/H = 0.441 Vol./W^3 = 0.288
PAVILION
CROWN
Addition # 13 - Cut this in refractive indexes 1.62 to 2.14 with no changes. This is not hard to cut, but takes a while. Lightly saturated materials work best.
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.
Related Articles
Tourmaline Value, Price, and Jewelry Information
How to Describe a Tourmaline Crystal by its C Axis
Gemstone Orientation for Beginners
Emerald Cutting Advice For Green Tourmaline And Rubellite
Never Stop Learning
When you join the IGS community, you get trusted diamond & gemstone information when you need it.
Get Gemology Insights
Get started with the International Gem Society’s free guide to gemstone identification. Join our weekly newsletter & get a free copy of the Gem ID Checklist!