The anionic group that occurs in carbonate minerals is the carbonate ion, which is represented as \( \text{CO}_3^{2-} \). This ion consists of one carbon atom (C) centrally bonded to three oxygen atoms (O).
In carbonate minerals, the carbonate ion typically bonds to various cations, which can include a variety of metal ions. Common cations that bond with the carbonate group include:
- Calcium (Ca)
- Magnesium (Mg)
- Sodium (Na)
- Potassium (K)
- Iron (Fe)
- Manganese (Mn)
The two most common carbonate minerals are:
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Calcite (CaCO₃): This mineral is a primary component of limestone and marble and is characterized by its rhombohedral crystal structure and variety of colors.
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Dolomite (CaMg(CO₃)₂): This mineral contains both calcium and magnesium and is significant in sedimentary rock formations.
These minerals are important in geological processes and have various industrial applications.