Cochise College          Photos of Minerals

                          Geology Home Page                

                          Roger Weller, geology instructor

                          wellerr@cochise.edu
                                  copyright 2006-R.Weller
 

Mineral Information on:
topaz

Chemical Group:    silicate

Chemical Formula:   
[Al(F,OH)2]AlSiO4

Color: colorless, white, pale blue, yellow, yellow-brown, brown, pink

Streak:  white           Luster:  vitreous

 

Hardness:  8        Specific Gravity:  3.5 to 3.6              

Cleavage: 1 direction, perfect, perpendicular to the length of the crystal

 

Crystal Forms and Habits:  Orthorhombic system
    Topaz forms prismatic crystals

Mineral Associations:  found in pegmatites

Identifying Characteristics:  Cleavage surfaces of topaz are very flat and smooth.

Uses: a gemstone

Occurrences:  Brazil, Mexico 

Toxicity:      when-swallowed- low       when inhaled- high

Additional Information: