Some types of schist are used as roofing, in ceramic glazes, in insecticides, as dimension stones and in potting soil mixes. Schists are metamorphic rocks that are characterized by thin sheets of minerals.
Schists do not have a specific mineral makeup. They are a type of metamorphic rock based on the structure of the mineral grains. In schists, the minerals form large, flat grains that are visible to the eye and will peel away in sheets.They are named for either the main mineral or an unusual mineral in the rock. Some examples of schists are:
- Mica schist
- Graphite schist
- Talc schist
- Chlorite schist
- Garnet schist
- Tourmaline schist
The mineral content of schist determines its uses. For example:
- Talc schist is used in ceramic glazes.
- Mica schist can be used to make vermiculite, a common component of potting soil.
- Greenish schist slabs — perhaps chlorite schist — were found by archeologists to have been used for roofing in the Bronze Age.