Seven Rattle: 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 "Seven Rattle"
Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)
Seven Rattle (DOME32.JRG)
By Jeff R. Graham
Copyright 2007
87.8% Light Return
Angles for R.I. = 1.62
71 facets + 7 facets on girdle = 78
7-fold, mirror-image symmetry
77 index
L/W = 1.026 T/W = 0.410 T/L = 0.399 P/W = 0.398 C/W = 0.339
H/W = (P+C)/W+0.02 = 0.757 P/H = 0.525 C/H = 0.448
Vol./W^3 = 0.280
PAVILION
CROWN
Addition # 13 - Cut this in refractive indexes 1.62 to 2.14 with no changes. This is unusual and because it is seven-sided, it will need a custom setting. It has a lot of flash and looks very unusual when cut.
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
Tourmaline Buying Guide
Difficult Gemstone Separations
Chrome Tourmaline Buying Guide
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!