Science glossary film: Limestone

A sedimentary rock composed mostly of calcium carbonate; relatively soft, and pale in color. It has been a popular building material for thousands of years, in part because it is so easy to work with. Limestone forms in warm, shallow seas, and almost always contains marine fossils, from microscopic shells to full skeletons.

It has been a popular building material for thousands of years, in part because it is so easy to work with. Limestone forms in warm, shallow seas, and almost always contains marine fossils, from microscopic shells to full skeletons.