Limestone is a sedimentary rock composed primarily of calcium carbonate (CaCO3), typically formed in marine environments from the accumulation of shell, coral, algal, and fecal debris. It is a key rock in the carbon cycle and is widely used in construction, agriculture, and industry. Limestone is important in understanding sedimentary environments and the geological history of carbonates.
Source Tucker, M. E., & Wright, V. P. (1990). “Carbonate Sedimentology.” Blackwell Science.