Mons Claudianus
Mons Claudianus was a quarry and Roman penal colony found in Egypt. It consisted of a slave settlement, a garrison and a quarrying site. Black Quartz diorite was mined for the Roman Empire where it was used as a building material. Mons Claudianus is located in the mountains of the Egyptian Eastern desert about midway between the Red Sea and Qena. Today tourists can see fragments of granite, with several artifacts such as a broken column.
References
http://www.yaroe.freeserve.co.uk/monsclaud1998/monsclaudianus.htm