The work deals with the FT-IR and micro- Raman spectroscopy study of the pseudo-amorphous and crystalline thermal phases in the composition of calcareous Iron Age pottery from the Galilee. The application of second-derivative and curve-fitting techniques improves the identification of the thermal phases in the composition of the pottery and makes it possible to analyze the pseudoamorphous phases which are formed during the firing of the clayey raw material to pottery. This technique makes it possible to distinguish between meta-smectite and metakaolinite and to estimate the firing temperature of the pottery. The Micro-Raman spectroscopy is sensitive to the structural degree of ordering of the thermal phases and enables point analysis of peculiar components in the composition of the pottery. Based on the spectroscopic study, it is concluded that the calcareous pottery contained large amounts of microcrystalline-recarbonated calcite mixed with the meta-clay. The large amount of recarbonated calcite in the pottery material and the relatively low firing temperature indicates that instead of sintering the clay, lime technology was used for the cementation of the calcareous vessels. This process took place after the firing by recarbonation of the decomposed calcite which leads to cementation of the vessels with microcrystalline calcite.
|Number of pages||11|
|Journal||Journal of Thermal Analysis and Calorimetry|
|State||Published - May 2011|
Bibliographical noteFunding Information:
Acknowledgements This research was supported by The Open University of Israel’s Research Fund (grant no. 31016). This support is gratefully acknowledged. The assistance of Galina Kaz is also highly acknowledged. The authors acknowledge the ‘‘CECOMO (Centre Commun de Microspectrométrie Optique)’’, vibrational spectroscopy platform established by the Institut de Chimie de Lyon and the Rhône-Alpes Région MACODEV program.
- Curve fitting
- Firing temperature
- Iron age
- Recarbonated calcite
- Second derivative