Geology Collection / Mineral Testing & Identification
The following are the tools and properties used to identify minerals. A mineral is a naturally occurring, usually inorganic, crystallized chemical element or compound, with a definite chemical composition which varies only within specific limits. Although compounds can be produced in the lab that have many of the characteristics of a mineral, because they are not naturally occurring they are not minerals. Nearly all minerals are inorganic, that is, not produced by living organisms. Minerals are crystallized, a solid with a definite internally ordered arrangement of atoms. Therefore, liquids and gases are not minerals. Because a mineral has a definite chemical composition, its composition can be expressed as a specific chemical formula. An example is quartz, which is composed of silicon and oxygen and has the formula SiO2.