Jaume Buxeda i Garrigós

Assessment of dissolution techniques for the analysis of ceramic samples by plasma spectrometry

Abstract In this study, 13 ceramic samples were subjected to dissolution using three different procedures: (a) acid attack in open PTFE vessels with a mixture of HF–HClO 4 , (b) fusion of the sample with lithium metaborate and (c) microwave digestion in PTFE bombs. The samples used in the study had been previously analyzed by neutron activation analysis (NAA), X-ray fluorescence (XRF) and X-ray diffraction (XRD) and they cover a wide range of ceramics fired in different atmospheres and temperatures as well as different mineralogical and chemical compositions. The effectiveness of each procedure is evaluated in terms of its ability to dissolve the various mineralogical phases of the samples, of the number of elements that can be determined and of the time needed for the whole scheme of analysis to be completed.

Identificación y significado de la calcita secundaria en cerámicas arqueológicas

La presencia de calcita como fase secundaria en ceramicas arqueologicas ha sido citada en diversos trabajos. Sin embargo, su identificacion e interpretacion han sido siempre problematicas. La calcita secundaria se presenta bajo diferentes habitos que deben reconocerse por microscopia optica de luz transmitida o por microscopia electronica de barrido. Mas problematica resulta su interpretacion segun se trate de un aporte completamente aloctono, parcialmente aloctono o la concurrencia de ambos factores. En el presente trabajo se exponen dos ejemplos en los que se identifica calcita secundaria, pero en los que es interpretada de manera diferente. La interpretacion depende de cada caso de estudio y requiere el concurso de diversas tecnicas =The presence of calcite as a secondary phase in archaeological ceramics has been mentioned in several papers. Nevertheless, its identification and interpretation has always been difficult. This calcite shows different morphologies which must be recognised by using optical microscopy or scanning electron microscopy. Additionally, its interpretation is related with its presence as completely aloctonous contribution, partially aloctonous contribution or both factors. This paper presents two examples where secondary calcite is identified though it is interpreted in a different way. The interpretation relies upon each case-study and requires different techniques

Chemical characterization of tin-lead glazed ceramics from Aragon (Spain) by neutron activation analysis

Abstract Majolica pottery was the most characteristic tableware produced in Spain during the Medieval and Renaissance periods. A study of the three main production centers in the historical region of Aragon during Middle Ages and Renaissance was conducted on a set of 71 samples. The samples were analyzed by instrumental neutron activation analysis (INAA), and the resulting data were interpreted using an array of multivariate statistical procedures. Our results show a clear discrimination among different production centers allowing a reliable provenance attribution of ceramic sherds from the Aragonese workshops.