“…Studies by Mossbauer spectroscopy (MS) of archaeological pottery suggested that the alterations observed in samples of different ages in the iron oxides may be connected with hydration processes in the pottery (Kostikas et al 1976, Danon et al 1976. Similarly, it has been suggested that the weathering of baked sediments and its effects on archaeomagnetic measurements are a consequence of physico-chemical processes leading to the presence of hydrated iron minerals in such sediments (Barbetti et al 1977, Sigalas et al 1978.…”