ON THE INFLUENCE OF DRYING AND FIRING OF CLAY ON THE FORMATION OF TRACE ELEMENT CONCENTRATION PROFILES WITHIN POTTERY

• Published in: Archaeometry Vol. 49; no. 3; pp. 495 - 509
• Main Authors: SCHWEDT, A., MOMMSEN, H.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.08.2007; Wiley-Blackwell
• Subjects: ALKALI ELEMENTS; ARSENIC; CALCITE; Ceramics; CLAY; CONCENTRATION PROFILES; Dating; DRYING; Environmental studies; Excavation and methods; FIRING; Geology and climatology; Laboratory methods; Methodology and general studies; NaCl; NEUTRON ACTIVATION ANALYSIS; Prehistory and protohistory; Typology, technology and attribute analysis; X-RAY DIFFRACTION; France; Centre; Sherd; Clay; Trace element; Firing; Migration; Lead; Influence; Ceramics; Neutron activation; X ray diffraction; Fir tree; Surface
• ISSN: 0003-813X; 1475-4754
• DOI: 10.1111/j.1475-4754.2007.00316.x

On experimentally fired briquettes made of five chemically and mineralogically different clays, trace element concentration profiles from the centre to the surface of the briquettes have been measured by Neutron Activation in order to examine if drying and firing of the clays lead to a mobilization and subsequent migration of single components within a sherd. Mineralogical changes during firing have been determined by X‐ray diffraction. Generally, no such migration could be found. For two clays, arsenic was lost from the briquette during firing, forming non‐constant concentration profiles. If NaCl is present in the clay paste, sodium migrates towards the surface. Additionally, in the special case in which the presence of NaCl coincides with that of calcite, the heavier alkali elements evaporate, forming significant concentration profiles within the sherd.