Limestone Photo courtesy of Field Museum, Chicago Limestone Limestone is a sedimentary rock composed of calcium carbonate.
Most limestone is gray, but it can be all colors ranging from white to black.
In Egypt, a lot of limestone was found in large quarries. That's why Egyptians used limestone for most of their building and sculptures. To find the best limestone , tunnels were dug into the base of the cliffs where there was a large amount of limestone. Then it could be cut into blocks. From there, the over 3 ton blocks were brought to the boats on the Nile River by large gangs of men.