Mineral are classified according to their chemical compositions. This results in a classification system that
groups minerals with similar properties together. The descriptions below describe the various mineral
These are pure substances that are not bonded with another type of atom. These are found alone on the
Example: diamond C
This group makes up 95% of the Earth’s crust. About 2,000 minerals make up this class, therefore this
large category has subdivisions. All silicates contain the silica tetrahedron.
pyroxenes- single chained (SiO3) n -2 micas- sheets (Si3O10)n-4
feldspars- 3D framework Si3O8 amphiboles- double chained (Si4O11)n -6
quartz- 3D framework SiO2 olivine- single tetrahedron SiO4 -2
An important source of metals. An oxide has a positive ion (cation) bonded to an oxygen. Be careful that
the oxygen is acting alone as the anion.
example- hematite Fe2O
An important source for ore minerals. Sulfides have a cation bonded to sulfur.
example- pyrite FeS2
These minerals contain the anion (SO4)-2
example- anhydrite CaSO4
Contains the complex anion (CO3)-2
example- calcite CaCO3
These minerals are the main source of phosphates for fertilizers. Contain the anion (PO 4)-3
The anion is a halogen, found in column 17 on the periodic table. (F, Cl,Br,I)
example- halite NaCl