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The article investigates the high-temperature interaction and sintering processes of samples of low-temperature firing high-alumina for technical ceramics based on the kaolin – alumina-containing component – dolomite ternary system and establishes the areas of formation of high-alumina body for technical ceramics on the ternary diagram. It is shown that as a result of high-temperature interaction, the formation of new crystalline phases of minerals occurs, including mullite, corundum, β-cristobalite, as well as in a small amount of anorthite and an amorphous glassy phase, which impart the necessary physical and mechanical properties to the fired sample. The area of optimal compositions for obtaining low-temperature sintering high-alumina ceramic bodies based on the kaolin – alumina-containing waste – dolomite ternary system was determined. [ABSTRACT FROM AUTHOR]

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The Pilgrimage Church of St. John of Nepomuk is a UNESCO World Heritage Site. This article presents the restoration work on a critically damaged parterre floor, involving the identification of the materials of the original tiles, the manufacture of replicas, and the design of the final tile layout. The original floor layout consisting of three-colored floor tiles in specific shapes was estimated by experts based on the remaining historical tiles in the peripheral parts of the church using calculations and computer simulations. The proposed tile-layout plan respects the original color and shape combination. The composition of the new ceramic mass and the color-decoration technique were based on ancient styles of ceramic technology. The successful renovation of the parterre floor tiles in the Pilgrimage Church of St. John of Nepomuk is a testament to the importance of preserving cultural heritage and helps to maintain the integrity of this historic site.

The chemo-mineralogical compositions, the formation of the crystalline phases of minerals, and the main properties of ceramic bodies containing steel-making furnace dust from metallurgical manufacturing were investigated on sintering at temperatures 950 – 1100°C. Iron-bearing dust stabilizes the structure and lowers the sintering temperature of a ceramic body. [ABSTRACT FROM AUTHOR]

A comprehensive investigation of the characteristics of clay from the Gurlan deposit showed that in a chemical formulation Gurlan hydromicaceous clay possesses a relatively high content of iron oxide and alkali oxides as well as fine dispersity and a small amount of finely dispersed free quartz, which make this clay readily fusible. It was also found that the Gurlan clay can be used as a low-temperature fluxing component, instead of cullet, erklez [glass stones], nepheline syenite, etc., in the development of ceramic compositions. [ABSTRACT FROM AUTHOR]

Class C fly ash has been receiving increasing attention due to the gradual transition of thermal power plants all over the world to the fluidized bed combustion technology with sulfur dioxide emissions capture. This research investigates the utilization of class C fly ash in fired ceramic materials with simultaneous efficient and novel containment of sulfur dioxide emissions in the flue gas during firing. A number of experiments were conducted by addition of sodium water glass with different molar ratios of SiO2:Na2O, sodium carbonate, and different ratios of sodium carbonate to water glass to the class C fly ash to examine the optimal combination and quantity for the creation and formation of the mineral phase haüyne which resulted in reduction and containment of SO2 emissions. Results revealed that a 12% dose of sodium water glass with a low molar ratio of 1.7 (SiO2:Na2O) combined with class C fly ash was more effective in the formation of haüyne and the resulting decrease of SO2 in the flue gas was more substantial. The newly formed mineral phase haüyne was identified by an X-ray diffraction analysis and scanning electron microscopy with energy dispersive X-ray spectroscopy. Outcomes reveal a potential for utilization of class C fly ash in the fired materials by containment of sulfur dioxide into their structure. [ABSTRACT FROM AUTHOR]

Purpose. The research focuses on the improvement of local clay-based ceramic pottery bodies from Alas Angker in Buleleng Regency in Bali. The main purpose is to utilize the clay which meets the standards of ceramics such as smooth and hard earthenware, especially to reduce its water absorption property. Methods. Firstly, the clay is analyzed for its physical and chemical composition. Two ceramic body formulations are made using the clay with the BWNAA1 and BWNAA2 codes. The specimens are measured in terms of clay ceramics properties including plasticity, dry shrinkage, firing shrinkage and water absorption. The cracked ceramic products are also analyzed for a comparison. Findings. The ceramic properties show similar results, except for the water absorption percentage. The BWNAA2 code formulation has lower water absorption rate by 10.8% and meets the requirements for the type of smooth and hard earthenware body in compliance with the national standard SNI:7275-2018. The water absorption rate is about half of the existing products, which is effective in avoiding the problem of cracks. Originality. Comparison of the existing ceramic products and specimens made in this study shows a significant difference in water absorption and crack growth. Adding a certain amount of kaolin, feldspar, ball clay and quartz sand has significantly reduced the water absorption rate of ceramic bodies. Practical implications. This research can be a potential solution to increase the quality of ceramic pottery products in the vicinity of Buleleng Regency which use the clay of this kind. [ABSTRACT FROM AUTHOR]

This work intends to study a set of Hispano-Moresque tile fragments from the Lisbon Roman Theatre Museum collection. The chemical and morphological characterization of the glazes and the ceramic body was presented and also the mineralogical characterization of the latter. The glazes are plumbic, being the opacity of the white and blue colors due to SnO2 (4-11 %). The other colors present amounts of SnO2 lower than 2 %. The ceramic body is typical of calcite-based pastes with CaO between 16-28 % and Fe2O3 between 4-5 %, the latter being responsible for the cream/ rose color. The mineralogical study identified wollastonite, calcite, diopside and calcic plagioclases. The results indicate that the firing temperature was generally around 1000 ºC while in some cases it was probably closer to 900 ºC. Physical characterization revealed values of 30-42 % for open porosity, a bimodal pore size distribution, a maximum water absorption of 16-26 % and a water absorption coefficient by capillarity of 1,5-6,1 kg·m-2·h-1/2.

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]

Copyright of Anadolu University Journal of Art & Design / Sanat & Tasarım is the property of Anadolu University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Conservar Património is the property of Associacao Profissional de Conservadores-Restauradores de Portugal and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)