This collection presents some of the most common rocks and rock forming minerals. Minerals are the fundamental constituents of most rocks and they form under specific natural conditions and factors that include heat, pressure and chemistry. For a substance to be called a mineral, it has to be naturally occurring, a crystalline solid and have a chemical composition that can be defined within narrow confines. A mineral will also be characterized by distinct physical properties.
In excess of 4500 minerals are known to man but the majority of these minerals are rare and less than 40 form the vast majority of all rocks.
To identify minerals, geologists can examine a range of properties including physical attributes such as color, luster, hardness and the transmission of light under a microscope as well as the chemical composition of the minerals involved.
This site can be used interactively to identify a mineral based on its physical properties such as hardness, color, streak and luster.
To see other collections that the AU Library has to offer please visit the Digitization Portal.
Updated February 26 2015 by Student & Academic Services