
Fanned Triangle: 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 "Fanned Triangle".
Quartz (Amethyst, Citrine, Ametrine, Smokey, Rose)

Fanned Triangle (QTZ40.JRG)
By Jeff R. Graham
Copyright 1994
88.3% Light Return
Angles for R.I. = 1.54
52 facets + 15 facets on girdle = 67
3-fold, mirror-image symmetry
96 index
L/W = 1.028 T/W = 0.303 T/L = 0.295
P/W = 0.392 C/W = 0.213
H/W = (P+C)/W+0.02 = 0.625
P/H = 0.627 C/H = 0.341
Vol./W^3 = 0.211
Addition # 1 - This design is fairly hard to cut and takes some work and attention to detail. Cut in refractive indexes 1.54 to 1.93 with no changes. Light material makes the best stone, 1-12cts.
![]()
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
Related Articles

Rose Quartz Value, Price, and Jewelry Information

Ametrine Value, Price, and Jewelry Information

Amethyst Gem, Price, and Jewelry Information

Citrine Value, Price, and Jewelry Information
Latest Articles

800 Years of Mogok: A Celebration in Tenuous Times

What is the Average Gemstone Faceting Yield?

Pyroxmangite Value, Price, and Jewelry Information

How to Identify Emerald Simulants and Synthetics

Never Stop Learning
When you join the IGS community, you get trusted diamond & gemstone information when you need it.





