Cochise College          Photos of Minerals

                          Geology Home Page                

                          Roger Weller, geology instructor

                                  copyright 2010-R.Weller


Mineral Information on:

Chemical Group:   oxide

Chemical Formula:  

Color:      grayish black, black                                                                   

Streak:    brownish black


Luster:  sub-metallic


Hardness:  5 to 6               Specific Gravity:    6.45           

Cleavage:  none


Crystal Forms:

Habits:  acicular, botryoidal, fibrous, reniform

Mineral Associations:

Identifying Characteristics:

Uses: manganese ore

Occurrences: France; Germany; England; Brazil; Arizona, Virginia, Michigan 

Toxicity:      when-swallowed-                            when inhaled-

Additional Information:  primary constituent of psilomelane