Opposed Beryl : 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 "Opposed Beryl"

0

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

Opposed Beryl (MC10.JRG) 2.08 carat seafoam Beryl
By Jeff R. Graham
Copyright 1999
82% Light Return
Angles for R.I. = 1.56
25 facets + 12 facets on girdle = 37
2-fold, mirror-image symmetry
96 index
L/W = 2.000 T/W = 0.917 T/L = 0.458
H/W = 0.732
Vol./W^3 = 0.751

Addition # 4 - This can be hard to cut the first time. It is a variation on the Vargas opposed bar. I designed it for longer narrow crystals (Tourmaline, Beryl). Establishing the proper L/W with a preform is a good idea. Cut the girdle facets as evenly as you can into thirds, you will probably have to do some adjusting to get this one finished, but it is well worth it. This works well in Tourmaline, and Topaz… Cut this in R.I. 1.56 to 2.14 (86.5%) 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!