Cochise College          Photos of Minerals

                          Geology Home Page                

                          Roger Weller, geology instructor

                                  copyright 2005-R.Weller

Mineral Information on:

Chemical Group:  carbonates

Chemical Formula: 

Color: colorless, white, gray, greenish, pink, yellowish brown

Luster:  vitreous to pearly  

Transparency:  transparent to translucent

Hardness:  3.5 to 4               Specific Gravity:  2.85                  Streak:  white

Cleavage:  rhombohedral, 3 directions           Fracture:   sub-conchoidal


Crystal Forms and Habits: Trigonal system
     Crystals are commonly rhombohedrons.
     Saddle-shaped curved crystals are common.
     Often in massive form, similar to limestone.

Mineral Associations:  Specimens from the Tri-State district  often have
     chalcopyrite crystals with the dolomite.

Identifying Characteristics:  Closely resembles calcite but reacts slower with
     the application of cold dilute hydrochloric acid than calcite.

Uses:  In pill form as a calcium source
    Also used for a building and ornamental stone

Occurrences:  Tri-State district, and Penfield Quarry, New York 

Toxicity:      when-swallowed- low         when inhaled- moderate

Additional Information: