Key Points
Key Points: Minerals
- Rocks are made of minerals; some rocks, like limestone, have one mineral, but most contain many minerals in different proportions.
- Though over 2000 minerals are identified, only a few are common and form most rocks.
- The properties of minerals (colour, hardness, crystal form, lustre, density) depend on the physical and chemical conditions of their formation.
- Geographers study minerals for their distribution and economic use, while geologists study their formation, age, and composition.
- Minerals are classified as metallic and non-metallic; ores are minerals from which metals are extracted (e.g., bauxite → aluminium).
