
Purple Cross: 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 "Purple Cross".
Tanzanite (Zoisite, Thulite)

Purple Cross (TANZ5.JRG)
By Jeff R. Graham
Copyright 1993
82.7% Light Return
Angles for R.I. = 1.69
69 facets + 12 facets on girdle = 81
4-fold, mirror-image symmetry
96 index
L/W = 1.000 T/W = 0.499 T/L = 0.499
P/W = 0.445 C/W = 0.220
H/W = (P+C)/W+0.02 = 0.685
P/H = 0.650 C/H = 0.321
Vol./W^3 = 0.279
Addition # 3 - This design is good for lighter colored material (it will help darken) and has good flash. It is easy to cut and does not take a lot of time, 1 -6cts(good luck on finding clean Tanzanite in 6cts). This works in Peridot as well as Garnet too… Cut in refractive indexes 1.69 to 2.14 with no changes.
![]()
Random - Cosine - ISO
Detailed faceting instructions by Jeff Graham available at The Rock Peddler
Related Articles

Tanzanite (Zoisite) Value, Price, and Jewelry Information

A Beginner’s Guide To Common Gemstone Heat Treatments

10 Gemstones Rarer than Diamond: The Earth’s Scarcest Treasures

Exploring the Hidden World of Tanzanite Mining: A Journey into the Depths of Tanzania
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.





