Cochise College          Photos of Minerals

                          Geology Home Page                

                          Roger Weller, geology instructor

                          wellerr@cochise.edu
                                  copyright 2006-R.Weller
 

Mineral Information on:
turquoise


Chemical Group:    phosphate

Chemical Formula:   
CuAl6(PO4)4(OH)8.4H2O

Color:  sky-blue, bluish-green to apple green            Streak:  white to pale green

 

Hardness:  5 to 6        Specific Gravity:   2.6 to 2.8
 

Luster:  waxy                

Fracture:  conchoidal to smooth

Cleavage:  rarely seen because material is usually massive

 

Crystal Forms:  Triclinic system
      Crystals are very rare; usually dense, massive and cryptocrystalline
      Occurs as small veins or crusts

Mineral Associations:

Identifying Characteristics:

Uses: jewelry and carvings

Occurrences: a secondary mineral found often in the weathered zone of a
copper deposit. The key ingredient needed is a phosphate source which may
be apatite in decomposing feldspar.