Granite is a coarse-grained igneous rock. This was used on the interior walls of the pyramids.

The amount and type of feldspar in granite can determine its color. This pink granite was used inside in the chambers.

Limestone was the main type of stone used in building. This is what covered the outside, as well as lower-quality limestone for the inner core. The average block weighed 2.5 tons.

How were the Great Pyramids built?

sources: Archaeology.org, AtlantisOnline

Scientists still do not have an exact answer about how the Great Pyramids were built. One theory is that Egyptians gathered stones of granite, lime-stone and pink granite from the Nile River region and tranported them on sliding logs. They would often create mud in front of their path to make the stones move smoother. The actual pyramid, some believe, was built using external ramps going up the side of the pyramid, then as the pyramid grew, the ramps continued up the side in a corkscrew formation. The builders would drag the stones up the slightly inclined ramp and place them on the outside of the pyramid.These ramps could not be too steep or the men would not be able to haul the stones up them.

GeoFactsNational Geographic