Cochise College          Photos of Minerals

                          Geology Home Page                

                          Roger Weller, geology instructor

                          wellerr@cochise.edu
                                  copyright 2007-R.Weller
 

Mineral Information on:
andalusite


Chemical Group:  silicate

Chemical Formula: 
 Al2SiO5

Color: variable, white, gray rose-red, brown

Luster:  vitreous to dull  

Transparency:  translucent
 

Hardness:  7.5           Specific Gravity:  3.15               Streak:  white

Cleavage:  one direction          

 

Crystal Forms and Habits: Orthorhombic system
     Crystals are commonly prismatic with nearly square cross sections.
     Crystals are often rounded.
     Cross sections of crystals have carbonaceous inclusions in a cross-patter: variety chiastolite.

Mineral Associations:  found in contact metamorphic shales


Identifying Characteristics: 

Uses:  Used in the manufacture of spark plugs.

USA occurrences: 
California
     Dalton, Madera County
     White Mountain, Mono County
Massachusetts
     Lancaster
New Hampshire
     Mt. washington

WORLD-WIDE occurrences:
South Africa
China 
Brazil
     Arrasuai, Minas Gerais
Australia
     Broken Hill

Toxicity:      when-swallowed- low         when inhaled- high

Additional Information: