Vitrification of basalt orthostats and mud building components from Tilmen Höyük (south-eastern Turkey): an experimental and geoarchaeological approach

Finds of basalt orthostats and mud building components from the archaeological site of Tilmen Höyük (south-eastern Turkey, early 2nd Millenium BC) preserve a glassy crust formed by vitrification of the material. It is proposed that such features are related to destructive fire events, which destroyed the wooden building elements and burned natural stones. The geoarchaeological and experimental approach confirms this hypothesis. The geochemical composition of experimental melts is comparable to that of natural basalts. Spot analyses evidence the heterogeneity of the melts, especially for mudbricks and ceiling plasters. It is concluded that the investigated finds were subjected to strong burning under oxidising conditions reached during a violent fire. Temperatures similar to those derived by experimental melting (1180–1195 °C) were likely reached in the fire at Tilmen in order to produce the glass observed.