Many of the pyramids were built with a number of different stone materials. Most of the material used was fairly rough, low grade limestone used to build the pyramid core, while fine white limestone was often employed for the outer casing as well as to cover interior walls, though pink granite was also often used on inner walls. Basalt or alabaster was not uncommon for floors, particularly in the mortuary temples and as was mudbricks to build walls within the temples (though often as not they had limestone walls).
Egypt is a country rich in stone and was sometimes even referred to as the "state of stone". In particular, Egypt has a great quantity of limestone formation, which the Egyptians called "white stone", because during the Cretaceous period Egypt was covered with seawater. The country is also rich in sandstone, but it was never really used much until the New Kingdom.
Limestone seems to have first been employed in the area of Saqqara, where it is of poor quality but layered in regular, strong formations as much as half a meter thick. This limestone is coarse grained with yellow to greenish gray shading. The layers are separated from each other by thin layers of clay and the coloration may vary according to layer. It could often be quarried very near the building sites, and quarries have been found at Saqqara, Giza, Dahshur and other locations.
