Tanzanite Photos              
Cochise College                                                           
Photos of Gemstones
Transparent Gemstones
Geology Home Page
Roger Weller, geology instructor                       



last edited:  11/11/17    number of photos: 18
Tanzanite is zoisite, Ca2Al3(SiO4)3(OH)
hardness: 6.5 to 7


lectures on tanzanite
Tanzanite- Linda Coe 

faceted tanzanite
tanzanite, faceted:  A  B  C  D  E  F  G
tanzanite, faceted-tray of stones: 

tanzanite, faceted-simulated tanzanite:  A

tanzanite in jewelry
tanzanite rings:  A B C D E  F  G  H 

tanzanite beads:  A

Photos are copyright free for non-commercial educational uses. 
Just credit photos to R.Weller/Cochise College.
copyright 2017-R.Weller                                                                       

Special notes:
Depending upon the orientation in which tanzanite is faceted,
it can either be a sapphire blue, an amethyst, or a grayish pale
green due to its pleochroism.
The intense blue color is the preferred orientation.
Vanadium is at least partially responsible for the color. 
Brownish crystals of this material are heat treated to
produce the sought after purple-blue color.

Location of the source of gem quality tanzanite is the Umba Valley
near the Usumburu Mountains, Tanzania near the Kenya border.