Pastes, ceramic

Cross, L.E. and Newnham, R.E. (1986) History of Ferroelectrics, in High-Technology Ceramics, Past, Pre.ient and Future, ed. Kingery, W.D. (American Ceramic Society, Westerville, Ohio) p. 289. 

Nolis, M.R. (1986) in High-Technology Ceramics, Past, Present and Future, vol. 3, ed. 

Masse,/. mass substance composition material stock batch assets Founding) dry sand Ceram.) paste Paper) pulp Elec.) earth, groimd ( Mass) measure, dimension, manner. 

When the same ceramic paste that is used for making terracotta is fired at higher temperatures (above 950°C), the material obtained is known as earthenware (see Fig. 55). Earthenware is more vitrified and therefore less porous and stronger than terracotta, although it is also opaque. Its porosity generally varies within the range 5-10%. Earthenware is often glazed. 

Neff, H. (ed.) (1992), Chemical Characterization of Ceramic Pastes in Archaeology, Monographs in World Archaeology, Vol. 7, Prehistory Press, Madison, WI. 

Rands, R. L., Bishop, R. L., Aspects of Ceramic Paste Composition and Trade in the Palenque Region, Chiapas and Tabasco, figures 4e, f, University Museum, Southern Illinois University, Carbondale, 1975. 

Natural teeth exhibit blue-white fluorescence in the long-wavelength UV [5.435]-[5.437]. Luminescent pigments are used to imitate this phenomena in artificial teeth. They are added to the ceramic paste at a concentration of 0.3-0.5 wt%. Yttrium silicates doped with cerium, terbium, and manganese give the best results [5.438]. The excitation maximum of these phosphors is in the range 325-370 nm. The fluorescence color of the teeth can be varied by changing the concentration of activators. 

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. 

Figure 5. Principal domponents analysis of the ceramics pastes from Mesopotamia. The ellipses represent 90% confidence intervals.

One of the more obvious examples of this interaction involves the addition of temper to a clay matrix (temper may be another clay, but is more often a nonplastic material). The effect of tempering varies a relatively pure material, such as quartz, may reduce elemental concentrations in a ceramic paste by a constant proportion (49). Addition of other kinds of temper or clay will result in a complex relationship of dilution and enrichment (14, 25, 50). Because elemental concentrations in sediments vary depending upon grain size (e.g., references 51-53), the size distributions of the added nonplastics also contribute to compositional complexity. If behavioral inferences are to be drawn, the culturally induced elemental variation arising from texture and temper differences among pottery produced from a single clay resource requires more than simple grouping and summary statistics. 

Hypothetical ceramic paste mixtures are generated from clays and tempers of known concentrations by calculating elemental concentrations according to... 

Heated Mineral Mixtures Related to Ancient Ceramic Pastes... 

Several studies of the effects of heating on pure clays have been reported in archaeological literature, but very little systematic work has been done on the effects of admixed mineral impurities upon the clays that constitute ceramic paste. The purpose of this chapter is to study the controlled firing of four measured mixtures of the clays, kaolinite and montmorillonite, with the common carbonates, calcite and dolomite. 

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