List the five characteristics that define a mineral. Based on the accepted definition of a mineral, completely describe why or why not the following materials might be called a mineral: window glass, emerald, water, table salt, synthetic opal, wood, amber, and granite.
Minerals
Window glass: Window glass is not a mineral because it is not naturally occurring. It is made by humans from a mixture of sand, soda ash, and limestone.
Emerald: Emerald is a mineral because it meets all five of the criteria. It is naturally occurring, inorganic, solid, has a crystalline structure, and has a definite chemical composition (Al2Be3Si6O18).
Water: Water is not a mineral because it is not a solid at room temperature and pressure.
Table salt: Table salt is a mineral because it meets all five of the criteria. It is naturally occurring, inorganic, solid, has a crystalline structure, and has a definite chemical composition (NaCl).
Synthetic opal: Synthetic opal is not a mineral because it is not naturally occurring. It is made by humans from a mixture of silica and other minerals.
Wood: Wood is not a mineral because it is organic and does not have a definite chemical composition.
Amber: Amber is a mineraloid, which is a substance that has many of the characteristics of a mineral but does not meet all of the criteria. Amber is naturally occurring, inorganic, and has a crystalline structure. However, it does not have a definite chemical composition.
Granite: Granite is a rock, which is a mixture of two or more minerals. Granite contains the minerals quartz, feldspar, and mica.
Here is a table that summarizes the information above:
Material | Mineral | Reason |
---|---|---|
Window glass | No | Not naturally occurring |
Emerald | Yes | Meets all five criteria |
Water | No | Not a solid at room temperature and pressure |
Table salt | Yes | Meets all five criteria |
Synthetic opal | No | Not naturally occurring |
Wood | No | Organic and does not have a definite chemical composition |
Amber | Mineraloid | Naturally occurring, inorganic, and has a crystalline structure, but does not have a definite chemical composition |
Granite | No | Rock, which is a mixture of two or more minerals |
The five characteristics that define a mineral are:
- Naturally occurring: Minerals must be formed naturally, not by human intervention.
- Inorganic: Minerals must be inorganic, meaning that they are not derived from living organisms.
- Solid: Minerals must be solids at room temperature and pressure.
- Crystalline structure: Minerals must have a definite crystalline structure.
- Definite chemical composition: Minerals must have a definite chemical composition.