Ancient pottery composition

From the correlation between the ancient pottery and modern clay one can draw several significant conclusions in addition to the most immediately obvious one that the matching ancient pots were locally made. The amount of temper in the ancient pottery, as evidenced by our comparison with the clay source, has not diluted or otherwise significantly altered the compositional pattern of the ceramic. Also the pottery must not have significantly changed in composition during burial. In addition we observed a small but significant difference between the composition... 

Table VII. Comparison of Concentration Means and Group Standard Deviations of Compositional Groups of Ancient Pottery Specimens...

The fundamental goal in the production and appHcation of composite materials is to achieve a performance from the composite that is not available from the separate constituents or from other materials. The concept of improved performance is broad and includes increased strength or reinforcement of one material by the addition of another material. This is the well-known purpose in the alloying of metals and in the incorporation of chopped straw into clay for bricks by the ancient Egyptians and plant fibers into pottery by the Incas and Mayans. These ancient productions of composite materials consisted of reinforcing britde materials with fibrous substances. In both cases the mechanics of the reinforcement was such as to reduce and control the production of cracks in the brittle material during fabrication or drying (2). 

A specific feature of the CEMS technique is the possibility for nondestructive testing of the surface composition of paintings, ancient coins, and pottery or other valuable objects. Wagner et al. [445] have investigated Celtic gold coins (from the time period 480-15 b.c.) and have shown that the surface of the coins consist of two phases, one of which is strongly eiuiched in gold compared to the bulk composition. 

Common ancient ceramic materials often found in archaeological excavations, such as fired brick and pottery, were made mostly from a mixture of a secondary clay and fillers. The nature, composition, and properties of clay have been already discussed the nature of the fillers, the changes undergone by the clay as well as by the fillers during their conversion to ceramics, and the unique properties of ceramic materials, are reviewed in the following pages. Attention is drawn also to studies that provide information on the composition and characteristics of ancient ceramic materials. 

An examination of the potential for provenance studies of variation in mineralogical and chemical composition on very old ceramic assemblages (of ancient Japanese pottery and of Mesoamerican plumbate pottery surfaces) has been performed by LA-ICP-MS. Results suggested that the region s geological complexity may inhibit successful provenance studies of ceramics.9-11... 

The concept of modeling tends to limit discussions of a best number or group of elements to use in compositional analysis (cf. 65, 66). What may be useful for one problem may not be useful for another. For example, at the global level of analysis, chromium concentration is an important regionally sensitive discriminator of ancient Maya pottery in the southwestern lowlands of Chiapas, Mexico. Yet, at the intraregional level of investigation, the range of variation frequently confuses rather than contributes to the local level of refinement. 

Glossy surfaces are obtained by dipping or painting the ceramic body with a slip, which is actually a diluted clay mixture with a similar composition to the body clay. Ancient Greek and Roman pottery are well-known examples for this technique. 

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