Opposed Bar 1.50: Faceting Design Diagram


Successful tips and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called "Opposed Bar 1.50"

0

Tourmaline (Achroite, Dravite, Rubellite, Indicolite, Verdelite, Siberite)

Opposed Bar 1.50 (MC22.JRG) 12.58 carat bi-color Tourmaline
By Jeff R. Graham
Copyright 1999
88.4% Light Return
Angles for R.I. = 1.62
17 facets + 8 facets on girdle = 25
2-fold, mirror-image symmetry
96 index
L/W = 1.500 T/W = 0.862 T/L = 0.575
P/W = 0.482 C/W = 0.212
H/W = (P+C)/W+0.02 = 0.714
P/H = 0.675 C/H = 0.297
Vol./W^3 = 0.634

Addition # 4 - This cut easy and can be almost any L/W with no changes. It works well in Tourmaline that is dark or closed on the "c" axis. You can cut the corners in or leave them pointed, 1cts and up... NOTE: P5 is optional. Cut this in R.I. 1.62 to 1.76 without changes.


Random - Cosine - ISO

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.

Never Stop Learning

When you join the IGS community, you get trusted diamond & gemstone information when you need it.

Become a Member

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!