Clay pastes ceramics

In the leaflet Keramik auf der Spur of the Tourist Information Centre in Hohr-Grenzhausen you can find four circular walks from the Keramik Museum . All walks lead past ceramic workshops and companies which produce various products, both functional as well as artistic. With the help of the book Keramik, ein Leitfaden durch das Kannenbackerland you can find clay pits or producers of heat-resistant systems and ceramic machines... 

THE USE OF FIRE TO transform CLAY PASTE into solid ceramic vessels may have been one of the earliest efforts at chemistry. Since the earliest times, pottery has been made by using clays formed by the weathering of rocks. Sedimentary deposits containing clay minerals also contain fragments of other minerals that are broken from the source rocks as they weather. The chemical composition of the sediments used as a clay source determined some of the characteristics of the pottery that was produced. 

Forming techniques used for clay-based ceramics require control of water content in the batch. Water content, in turn, affects the response of the clay during forming [27], As the water content of the batch increases, the yield point of the clay-water mixture, and thus the force required to form the desired shape, generally decreases [26], However, the relationship is complex and depends on the composition of the clay, its structure, additives to the batch, and other factors [14], One method for quantifying the behavior of clay-water pastes is to measure the plastic yield point as a function of water content [14], The water contents and maximum yield points in torsion are compared for several clays in Table 9. Kaolins and plastic fire clays require the least amount of water to develop their maximum plasticity, ball clays require an intermediate amount, and bentonite requires the most. 

Shiraki, Y. and Komaki, T., 1955, Smdies on clay-water system. (1-12) Visco-elastic properties of clay paste. Journal of the Ceramic Association of Japan, 63(708), 194—197. 

Trace-element analysis, using emission spectroscopy (107) and, especially, activation analysis (108) has been appHed in provenance studies on archaeological ceramics with revolutionary results. The attribution of a certain geographic origin for the clay of an object excavated elsewhere has a direct implication on past trade and exchange relationships. 

The following section focuses on the variability of the clay bodies or pastes of the glazed ceramics previously characterized by LA-ICP-MS and LA-TOF-ICP-MS. The purpose of this study is to compare the variation in the ceramic pastes with the different glaze decorative technologies through time. The variability in the ceramic pastes will be characterized through instrumental neutron activation analysis (INAA) and petrographic analysis. 

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