The outside of a pyramid was made almost entirely of limestone. The limestone that was quarried was built around the interior pyramid and allowed the pyramid to have an incredibly bright shine to it. Some say that the shine of the pyramids was visible all the way to Jerusalem. Unfortunately, most of the limestone was either stolen or destroyed over time, and the majority of most pyramids' facades now consist of the inner shell.
The inner shell of the Pyramid of Giza is mainly composed of granite. Interior sections of the pyramid are also composed of this material. For instance, the King's Chamber, where the king was buried, is also built from slabs of granite. Many slabs of granite were required to build the pyramid's interior rooms.
Some chambers of the pyramids were made with a special kind of granite known as pink granite. Pink granite was used for a number of different parts of the pyramid, including the lower sections of chambers, and to build the sarcophagi that held the kings and other ancient nobles of Egypt.
The Pyramids of Giza consist of numerous different blocks fit together. The blocks of limestone and granite came from local quarries, and were shipped to the pyramid site for construction. Many of the building blocks weighed approximately 2.5 tons, with bigger blocks having to be sent via boat through the Nile. Experts estimate that the Pyramid of Cheops, the biggest pyramid, was made with almost 2,300,000 blocks of limestone.
One scientist argues that another material used in the pyramids was a very early form of concrete. Professor Michel W. Barsoum argued that the Egyptians created what were called in his work "geopolymers." These geopolymers were materials that consisted of sand, lime and clay, and formed a primitive cement. Critics argue that Barsoum may not have taken into consideration the restoration of the pyramids, and may have inadvertently tested modern concrete, but researchers are taking Barsoum's research into consideration.
