Part of the EASP Geology Walk Limestone is a sedimentary rock which can form in one of two ways: by being chemically precipitated from water or by the build-up of the hard parts of marine organisms. Fossiliferous limestone is of the second category. Certain marine organisms, such as coral, remove calcium carbonate from their watery environment to make the hard parts of their bodies. When the marine organisms die, these hard parts collect on the sea floor and become limestone. The fossil remains can be found embedded in samples of limestone. Department of Earth, Atmospheric, and Planetary Sciences
