Cochise College          Photos of Minerals

                          Geology Home Page                

                          Roger Weller, geology instructor

                          wellerr@cochise.edu
                                  copyright 2006-R.Weller
 

Mineral Information on:
sodalite


Chemical Group:    silicate  (feldspathoid)

Chemical Formula:    
3Na2Al2Si2O8.2NaCl

Color:    azure blue, but also white or pink            Streak:  white

 

Hardness:  6          Specific Gravity:  2.3              Fracture:

Cleavage:  (110) poor    Luster:  vitreous

 

Crystal Forms:  Isometric system

            forms small dodecahedron crystals, but usually massive

Mineral Associations: Can be formed by the alteration of nepheline by halite (NaCl)
    Sodalite is also considered to be a feldspathoid.

Identifying Characteristics:

Uses:  jewelry and carvings

Occurrences:  found in nepheline syenite type rocks; Bancroft, Ontario, Canada
     Best location is Princess Sodalite Mine, 2 miles east of Bancroft

Additional Information:  sodalite is on Ontario's emblem