Physiochemical Effects of SiC and ZrO2 Particle Fillers on the Properties of Enamel Coatings

The ceramic particles of SiC and ZrO2 are embedded as fillers in the enamel coating with varying contents of 0.03, 0.05, and 0.1 wt %, and the surface properties are measured. It is found that the addition of ceramic fillers indeed causes changes in surface properties. The roughness was influenced mainly by the particle size embedded. The contact angle decreased at 0.03 and 0.05 wt % and equivalent to that of no filler at 0.10%. Our analysis suggested that the contact angle is influenced by both surface roughness and surface morphology (with chemical composition). The microstructure and elemental analysis suggest that the chemical composition and shape of Al, Ce, Ca, and P-rich aggregates on the enamel surface are showing significant changes when fillers are added. It is observed that the Al- and Ce-rich aggregates decrease both in number and size as the filler content increases, and Ca-rich aggregates change their shape from needle to spot at 0.1 wt % inclusion. The washability is notably improved at 0.1 wt %, which corresponds to the content where the drastic microstructure change occurred. The examination of the contaminated surface revealed that the phosphate component in the contamination has reacted with the Ca-rich phase of the needle-shape during the process of burning, thus inhibiting an easy removal of the contamination. Therefore, the formation of the Ca-rich phase of the needle-shape on the enamel surface should be suppressed for easy-cleaning enamel coatings for cooking wares.

Exploring Immigrant Identities: The Link between Portuguese Ceramics and Sephardic Immigrants in 17th Century Amsterdam

During urban expansions around 1600 a new neighborhood, Vlooienburg, was created in the rapidly growing city of Amsterdam. This new district was not just inhabited by local people, but also by immigrants coming from different European countries. Among those immigrants there were Sephardic Jewish people, who had fled from the Iberian Peninsula due to the persecution perpetrated by the Spanish Inquisition. By studying the archaeological finds that have been recovered from cesspits at Vlooienburg, an attempt is made to gain more knowledge about the composition of different cultural, religious and social identities living together in this area. As a part of the study of the material culture from Vlooienburg, this paper will present a case study that explores the possible relationships between the mobility of Portuguese ceramics and the presence of Portuguese immigrants. The paper will examine the distribution of different Portuguese wares to establish whether there were significant differences in how these ceramics were acquired and used within seventeenth century households in Amsterdam. The main result of this study is the remarkable link between Portuguese coarse cooking wares and the presence of immigrant households.

Microstructural, Mineralogical and Petrographical Characteristics of the Medieval Ceramics from the Studenica Monastery (UNESCO World Heritage Site): Implications on the Pottery Technology and Provenance of The Raw Material

On the basis of optical microscopy, scanning electron microscopy with energy-dispersive spectrometry and X-ray powder diffraction analyses, we present detailed mineralogical and petrographical characteristics of 63 samples of cooking and tablewares, which originate from two Medieval horizons (S1 and S2) in the Studenica Monastery, as well as of three samples of clays regarded as possible pottery raw material. The composition of the ceramic matrix is compatible with the composition of local clay and clasts that reflect the geology of the Studenica’s surroundings. This indicates that almost all studied vessels are unequivocally made locally. However, four wares may represent imports because they show similarities with Byzantine sgraffito wares, and ceramics from the Peloponnese (13th century). In terms of technological and morphological characteristics, the studied pottery collection represents a standardized production. Firing temperatures, estimated according to the level of matrix crystallinity, mineral reactions, and the mode of the appearance of fracture surfaces, indicate that most of cooking wares were fired at 600–700°C. All glazed wares, including tablewares and cooking pots from both S1 and S2, were fired at minimum 800–900°C. Along with technological and morphological standardization the characteristics of the studied collection show knowledge of traditional skills as well as trends within the Byzantine artistic craft circle.