Cochise College          Photos of Minerals

                          Geology Home Page                

                          Roger Weller, geology instructor

                          wellerr@cochise.edu
                                  copyright 2006-R.Weller
 

Mineral Information on:
colemanite


Chemical Group:    borate

Chemical Formula:   
Ca2B6O11.5H2O


Color:  colorless, white, yellowish, grayish              Streak:   white

 

Hardness:  4.5          Specific Gravity:  2.42          

Fracture:   uneven        Tenacity:  brittle
 

Luster:  vitreous      Transparency:  transparent to translucent

Cleavage:  (010) perfect, (001) distinct

 

Crystal Forms:  Monoclinic system
        Often massive, granular

Mineral Associations:   other borate minerals

Identifying Characteristics:

Uses:  used in producing borate compounds

Occurrences:  California borax deposits

Toxicity:      when-swallowed- high         when inhaled- moderate

Additional Information: