A Preliminary study on material properties of the Zerzevan Castle, Turkey

Zerzevan is a recently discovered castle, situated on a rocky hill in the province of Diyarbakır, southeastern Turkey. Like many other Medieval defensive artifacts, Zerzevan Castle has also erected to protect the site against the incursions of enemies and to dominate the land. Zerzevan Castle, as a former military base of the Roman Empire, consists of such remains as churches, tombs observation towers, cisterns, arsenal, canals and city walls. The archaeological excavations conducted in the site revealed the existence of various underground structures, among them a temple of Mithraism, a mystery religion. The temple is considered as the first and unique Mithraeum located on the eastern border of the Roman Empire. The castle has been constructed by employing natural stones. Similar to that of the stone artifacts around the world, the Zerzevan Castle has also suffered from stone deterioration and stability problems. The present study aims to characterize stone used in the Zerzevan Castle as a building material. The study also aims to characterize the provenance of the stone material utilized in the monuments of that archaeological site. For this purpose, samples were collected from the building façade and stone quarry located on the site. The samples then used to determine their petrographic, chemical and some of the physico-mechanical properties. The preliminary results demonstrate that the stone employed in the construction of the Castle is calcitic dolomite. Moreover, the great similarities in chemical compositions of the samples collected from the building and the quarry indicate that the stone material employed in the construction was most probably extracted from the nearby quarries.