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TB: 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 "TB".

By Jeff R. Graham, updated on

Beryl (Aquamarine, Emerald, Helidore, Bixbite, Goshenite, Morganite, Golden Beryl)

"TB" (B31.JRG)
By Jeff R. Graham
Copyright 2001
84.2% Light Return
Angles for R.I. = 1.56
55 facets + 8 facets on girdle = 63
2-fold, mirror-image symmetry
96 index
L/W = 1.200 T/W = 0.729 T/L = 0.608
P/W = 0.620 C/W = 0.158
H/W = (P+C)/W+0.02 = 0.799
P/H = 0.777 C/H = 0.198
Vol./W^3 = 0.423

Addition # 5 - Notice when you cut the L/W=1.20 and the P1 tier it will meet at 96-24- 48-72. There are only four girdle facets for speed and yield. This will work in any R.I. from 1.54 to 1.76 (89.8%) with no changes.

 

 


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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