Mexico, ceramic compositional

A Ceramic Compositional Interpretation of Incense-Burner Trade in the Palenque Area, Mexico... 

Two samples, SC 37 and SC 38, assigned to the proposed Puebla production group, in fact come from the sealed context at the Metropolitan Cathedral. The significance of these two sherds is that they provide evidence of Puebla production of majolica ceramics before 1573. Two of the Fig Springs/San Juan Polychrome sherds, SC 46 and SC 52, excavated at the Sagrario, have the proposed Mexico City composition. On this basis, we propose that there may be two varieties of Fig Springs/San Juan Polychrome, one from Puebla and one from Mexico City. 

In Chapter 5, Olin and Blackman explain that differences in the chemical compositions of pottery are caused by both the use of temper and by chemical and mineralogical differences in the source of the clay. Olin and Blackman report on the continuation of their studies of majolica (a common earthenware pottery) from the Spanish Colonial period in Mexico. They used INAA as well as microscopic examination of the minerals to show that majolica produced in Spain could be distinguished from that produced in Mexico. Volcanic temper was present in the ceramics produced in Mexico, and the chemical analysis of these local ceramics suggested different production centers in Mexico. The discovery of a chemically distinct group of sherds added to the typological classifications of this pottery. 

It is logical to consider whether the majolica sherds which were found in Mexico City could have been fabricated of local clay. Fortunately data on clays and related pottery from the Valley of Mexico has been collected at Brookhaven National Laboratory over many years. The ceramic material, which had previously been anlyzed by Harbottle and Sayre in collaboration with other investigators, consisted of Precolumbian artifacts. The pottery and the clays from two archaeological sites within the Valley, Teotihuacan, and Tlatilco were all basically similar in composition, although the clays and pottery from the two separate sites could be diflFerentiated through a subtle multivariate statistical analysis. It is likely that the entire Valley of Mexico is underlain with clay bed of moderately uniform trace impurity composition, and hence if the composition of the Mexico City majolica sherds was similar to that of ceramics and clay from Teotihuacan or Tlatilco, it would be probable that the majolica was fabricated from clays originating somewhere within the Valley of Mexico. 

The chemical composition of imported, European-made majolica is different from that of majolica made in Mexico (J). The difiFerences in the concentrations of the oxides of cerium, lanthanum, and thorium are eaily recognized the Spanish majolica contains approximately twice as much of each of these oxides as the Mexican majolica. The mineralogical composition, too, of the pottery products of each area is fundamentally different and can easily be identified. The ceramic types and their origins, based on archaeological arguments, can be found in Table I. 

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