Clay: An important raw material for prehistoric man

Early techniques of making pottery can be investigated by Fe-57 Mossbauer s pectroscopy. Iron is generally present in unpurified clays in concentration s of several percent. During firing, the iron undergoes characteristic chan ges of its chemical and physical state, depending on the kiln atmosphere an d on the maximum firing temperature reached. These changes can be followed by Mossbauer spectroscopy. Firing techniques can often be reconstructed whe n spectra of laboratory and field fired samples are compared with those obs erved in ancient sherds.