Classification of minerals Systematic classification of minerals is based on the chemical composition of the mineral.

 Over 2000 minerals are presently known to exist and new ones are still being discovered. Fortunately no more than a few dozen are abundant.  Collectively these abundant minerals make up the bulk of the Earth’s rocks and are classified as “rock forming minerals”  Only 8 elements make up the bulk of these minerals with oxygen and silicon being 1 and 2

Mineral Groups  1. Native elements – are those found uncombined chemically in nature. i.e. gold, copper, silver, sulfur

Oxides  Oxide minerals contain one or more metals combined with oxygen. (O 2 )  i.e. hematite (iron oxide)

Sulfides  Minerals containing atoms of a metal and sulfur. i.e. galena (PbS)

Sulfates  Minerals containing atoms of a metal and sulfate. (SO 4 ) i.e. gypsum (CaSO 4 -2H 2 O)

Halides  Halides contain the halogen elements fluorine, bromine, chlorine iodine. i.e. halite (NaCl )

Carbonates  Carbonates are minerals that contain CO 3 and the atoms of a metal. i.e. calcite (CaCO 3 )

Hydroxides  Hydroxides are minerals that contain (OH) and atoms of a metal. i.e. limonite  FeO(OH)- 2H 2 O

Phosphates  Phosphates are minerals that contain PO 4 and the atoms of a metal. i.e. apatite

Silicates  Minerals that contain SiO 4 and the atoms of a metal. ie feldspar  The silicate group is the most abundant group of minerals on Earth.