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The archaeometric analysis of a set of potsherds of black slip ware found at the site of Barikot (Swat Valley, north-western Pakistan), dated between the Indo-Greek and the Kushan phases (middle 2nd century BCE–middle 2nd century CE), was addressed to define the provenance of this pottery and to constrain the production technology of both the ceramic body and the black external slip in terms of raw materials used and firing conditions. A multidisciplinary approach, consisting in the petrographic, mineralogical, chemical and spectroscopic (Mössbauer) analyses, was used to define possible differences between sherds archaeologically classified as grey ware, northern black polished ware and black gloss ware. The composition of this ceramic class resulted quite homogeneous, indicating the use of similar clay materials (low-calcium and both potassium- and iron-rich) and preparation procedures, with one exception represented by the only black gloss ware analysed. When samples are considered in diachronic terms, a progressive change can be observed, mainly related to a progressive intensification of the clay levigation. The petrographic nature of medium and fine sand-sized inclusions indicates that the pottery was produced within the region and possibly in Barikot. As for its production technology, the mineralogical associations indicate that the firing temperature was in the thermal interval between 650 °C and 950 °C, while the presence of spinel-like minerals, maghemite and wustite suggests that the firing was in reducing conditions. Important differences were observed in terms of paste and slip preparation for the black gloss ware with respect to the grey ware and northern black polished ware, which were interpreted also under an archaeological viewpoint. [ABSTRACT FROM AUTHOR]

For the purpose of chemical characterization, a selection of 29 ceramic fragments from the 11th to 15th century has been made from materials excavated in the Seville Alcazar Palace. The PIXE elemental analysis results indicated that the ceramic bodies can be divided into four groups. The XRD identification of the phases present in the bodies revealed differences in the firing temperatures. The PIXE analysis of the glazes revealed variable PbO and SnO 2 contents. The latter component was not detected in all the glazes. Cu, Co, Mn, Fe and Sb elements were associated with green, blue, black and yellow colours, respectively. Some glazes were covered by iridescent layers constituted by lead carbonate and phosphates due to alteration of the glazes. It was also possible to detail the microstructure and composition of the ultimate surface layers responsible for the lustre effect observed in two of the ceramic samples using PIXE and Rutherford backscattering spectrometry (RBS). [ABSTRACT FROM AUTHOR]

Research deals with the possibility to improve the properties of ceramic products by utilising the modifying additive of multi-walled carbon nanotubes (MWCNTs), mixed with carboxymethylcellulose (CMC), which has the properties of dispersant, (MWCNTs + CMC). It was found that after the insertion of modifying additive (MWCNTs + CMC, sufficient to reach 0.0045 mass percent of MWCNTs in the overall formation mass) into ceramic products’ formation mass, plasticity as well as stability of the formation mass increase considerably and microstructure of semimanufacture changes. Density and strength of the semimanufactures become higher. Modified structure of the semimanufactures influences physical and mechanical properties of the burned ceramic bodies, as well as values of structure parameters. However, for the case when burning out sawdust additive is used in the composition of the formation mass, modifying additive has no noticeable influence on the properties of ceramic body. In this case, the absence of influence can be explained by considering that dry porous sawdust on the surfaces easier and more intensively absorb water dispersion with the particles of modifying additive, and therefore distribution of these particles in the formation mass is limited. Carbon nanotubes, adsorbed locally on sawdust particles, burn out together with sawdust. In such a way the positive influence of modifying additive is blocked. This interpretation was confirmed by the positive effect of modifying additive, when the other burning out additive–dispersed anthracite, which is distinguished by its hydrophobic properties, was introduced into the formation mass. [ABSTRACT FROM AUTHOR]

Abstract: Physico-mechanical properties (flexural strength, Young modulus, bulk density, change of dimensions, porosity) as well as the mineralogical composition were studied on samples with difference content of calcite after firing at 900, 1000, 1100 and 1200°C. It was found that anorthite and mullite are the main crystalline phases of the fired samples containing the calcite. The anorthite/mullite ratio depends on the firing temperature and the initial amount of calcite waste. The higher the temperature of the firing and the higher the amount of calcite waste, the more anorthite is created in the samples. Presence of calcite decreases sample contraction during sintering. Porosity decreases with the increase of the firing temperature, but the sample with the content of calcite 20wt% shows approximately constant porosity. Flexural strength and Young modulus of the reference sample and the sample with 10wt% of calcite waste increase in their value. These mechanical parameters increases very slightly for the sample with 20wt% of calcite waste. [Copyright &y& Elsevier]

Abstract: Eight findings of ancient ceramics (IX–X century) from Merv (currently Mary City – Turkmenistan) were sampled and studied from a scientific point of view, in order to classify them on the basis of their materic and technological content. They have been collected in a place 70km far from the Iranian border, on the ancient Silk Route and hence, in connection with Turkey, Afghanistan and Indo Valley. Different physico-chemical and analytical methodologies have been used for a detailed study of the mineralogical composition and the texture of the ceramic body, the material employed for coatings (slips, glazes and enamels) and decorations (chromophores and pigments). Optical (OM) and Scanning Electron Microscopy (SEM–EDS or WDS) measurements, carried out on thin and cross-sections, allowed an evaluation of the state of conservation of the findings, together with the presence of neo-formation phases (i.e. phosphates). These ceramics were characterized on the basis of the employed raw materials and the production technology, verifying and ascertaining differences and analogies. Finally, we have evaluated whether an exhaustive scientific description and characterization of these findings can be useful for proposing a historical contextualization. [Copyright &y& Elsevier]