IGS Background

Twist on “CH”: 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 "Twist on "CH" ".

By Jeff R. Graham, updated on

Garnet (Pyrope, Rhodolite, Almandine, Spessartite, Grossular, Demantoid, Tsavorite)

Twist on "CH" (GNETA5.JRG)
By Jeff R. Graham
Copyright 1997
78% Light Return
Angles for R.I. = 1.73
32 facets + 8 facets on girdle = 40
4-fold symmetry
96 index
L/W = 1.000 P/W = 0.446 C/W = 0.229
H/W = (P+C)/W+0.02 = 0.695
P/H = 0.641 C/H = 0.330
Vol./W^3 = 0.256

Addition # 2 - This is a nice change and is simple to cut. It is a little different twist on one of my early designs that a lot of cutters have told me they wanted more of. Cut in lighter material, 1/2-6cts. This works well in man-made Sapphire, YAG, and Spinel.


Random - Cosine - ISO

Detailed faceting instructions by Jeff Graham available at The Rock Peddler

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!