However, it can also contain other minerals and impurities in smaller amounts, including:

* Magnesium carbonate (MgCO3): This can be present in varying amounts, leading to different types of limestone like dolostone, which has a significant amount of magnesium carbonate.

* Silica (SiO2): Found as quartz or other silicate minerals.

* Iron oxides (Fe2O3, FeO): Contribute to the coloration of limestone, ranging from yellow to reddish brown.

* Clay minerals: Can be incorporated into the limestone during formation.

* Organic matter: May be present in some limestones, especially those formed from the accumulation of marine organisms.

The specific composition of a limestone rock can vary depending on its origin and geological history.