The glazed tiles of the Thomas Strobl stove: An achaeometric study

Abstract

Abstract The aim of this study is an in-depth characterization of the materials constituting the Thomas Strobl stove exposed in the Salzburg museum as archetype of a ceramic product very common in North Europe. The study improves the knowledge on the nature and origin of the materials used for the production of this type of ceramic product and to study the secondary minerogenetic process that have taken place. This study was commissioned by the Salzburg museum ordered this study in order to plan a restoration intervention that also agree to provide samples to proceed in the research. Multiple methodologies such as optical microscopy on thin section (OM), X-ray powder diffraction (PXRD), scanning electron microscopy analysis (SEM), energy-dispersion X-ray spectroscopy (EDS) and simultaneous thermal analyses (STA) were used for the study. The results showed interesting information about the origin and the nature of the raw materials used which, for the high values of alumina (27% Al2O3) detected, seem to be kaolinitic clays. The presence of sulphur and consequently the gypsum, seems to indicate the use of clays outcropping in the surroundings of Salzburg characteristics for the presence of lens of evaporitic rocks. In addition, the analyses identified three main groups of samples different for the calcium content: this findings seem to indicate that some tiles are copies or in any case non-original parts of the stove.