- Mineral – a naturally occurring inorganic element or compound with a fairly well-defined chemical composition and a specific crystal structure, Examples include quartz, feldspar, mica, garnet and calcite.
- Rock – a naturally occurring aggregate of one or more minerals, or a body of undifferentiated mineral matter. Examples include granite, basalt, limestone, and sandstone.
- Conglomerate – a sedimentary rock made up of large (greater than two mm) rounded clasts, or fragments of rocks and minerals. The space between the clasts is generally filled with smaller particles and/or a calcite or quartz cement that binds the rock together.
- Almandine garnet is the state mineral of CT.
- Magnetite, a magnetic mineral, used to be harvested off of CT beaches by rolling a giant lodestone down the beach and then scraping off the magnetite.