Aswan quarries

The stone quarries of ancient Egypt once produced quality stone for the building of tombs and temples and for decorative monuments such as sarcophagi, stelae, and statues. These quarries are now recognised archaeological sites. Ancient quarry sites in the Nile valley accounted for much of the limestone and sandstone used as building stone for temples, monuments, and pyramids. Eighty percent of the ancient sites are located in the Nile valley; some of them have disappeared under the waters of Lake Nasser and some others were lost due to modern mining activity.

Some of the sites are well identified and the chemical composition of their stones is also well known, allowing the geographical origin of most of the monuments to be traced using petrographic techniques, including neutron activation analysis.

Source: Wikipedia