IGS Background

72 Brilliant: Faceting Design Diagram


Detailed information and guide on Faceting Designs. A Faceting Design Diagram by Jeff R. Graham that presents various cuts, this one is called 72 Brilliant.

By Jeff R. Graham, updated on

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

72 Brilliant Graham Facet Design 172 Brilliant Graham Facet Design 2

72 Brilliant (DOME35.JRG)
By Jeff R. Graham
Copyright 2007
82.1% Light Return
Angles for R.I. = 1.62
64 facets + 9 facets on girdle = 73
9-fold, mirror-image symmetry
72 index
L/W = 1.015 T/W = 0.221 T/L = 0.218 P/W = 0.417 C/W = 0.326
H/W = (P+C)/W+0.02 = 0.763 P/H = 0.547 C/H = 0.427
Vol./W^3 = 0.257

PAVILION

CROWN

Addition # 13 - Cut in refractive indexes 1.62 to 2.14 with no changes. This is easy to cut and works well in light to medium saturated material. This is a nice cut for Tourmaline nodules.

72 Brilliant Graham Facet Design 3

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!