Fe3+ in pottery: Distinction of the use for cooking and production parameters

• Published in: Applied clay science 2016-08, Vol.129, p.88-91
• Main Authors: Mangueira, G.M., Teixeira, S., Silva, F.A., Franco, R.W.A.
• Format: Article
• Language: English
• Subjects: Ancient pan; Electron paramagnetic resonance; Fe3; Firing temperature; Pottery technology
• ISSN: 0169-1317; 1872-9053
• DOI: 10.1016/j.clay.2016.04.024

The estimated firing temperature and atmosphere in which a piece of pottery was produced can be identified by comparing the concentration of Fe3+ between the piece of pottery and clay with a similar chemical composition that were subjected to identical thermal treatments. This procedure was applied to modern pottery donated by indigenous people and to a set of archaeological pottery. The modern pottery that was used for cooking for two years exhibited higher Fe3+ concentrations than the clay that was fired at any temperature; thus, the parameters of production were not identified in this pottery. The same procedure can be used to identify the use of a piece of pottery as a pan. Of the set of 14 pieces of archaeological pottery examined in this study, 12 were able to have their production parameters identified, and 2 fragments were identified with Fe3+ concentrations that were higher than that of the fired clay, suggesting that these pieces were used as pans. The results of this study indicate that the concentration of Fe3+ can be used to determine if a piece of pottery was used for cooking; additionally, if a piece of pottery was not used for cooking, then the proposed method can identify the parameters of the piece of pottery's production. [Display omitted] •Fe3+ concentration can indicate if a piece of pottery was used for cooking.•The temperature, environment and time of firing pottery can be determined using EPR in pottery not used for cooking