Ancient Mesoamerican peoples harvested latex from Castilla elastica, processed it using liquid extracted from Ipomoea alba (a species of morning glory vine), and fashioned rubber balls, hollow rubber figurines, and other rubber artifacts from the resulting material. Chemical and mechanical analyses of the latex and of the processed rubber indicate that the enhanced elastic behavior of the rubber relative to the unprocessed latex is due to purification of the polymer component and to an increase in the strength and number of interchain interactions that are induced by organic compounds present in I. alba. These ancient peoples' control over the properties of latex and processed rubber gave rise to the Mesoamerican ball game, a central ritual element in all ancient Mesoamerican societies.

Copper Sources, Metaldepends on whether regional geologic formation processes have resulted in clearly delineated LI fields, as well as on the num-Prod uction, and Meta 1s Trade i n ber of deposits analyzed. We considered a deposit or mining region to qualify as a Late Postcl assi Mesoa me i ca potential source when the artifact signature fell within the ore field. T o determine

Metallurgy first appeared in Mesoamerica at about A.D. 800, introduced via a maritime route from Central and South America into West Mexico. During the initial period of the establishment of the technology (approximately A.D. 800 to between A.D. 1200 and 1300) technical links were closest with the metallurgies of Ecuador, Colombia, and lower Central America. During the second period of West Mexican metallurgy (A.D. 1200–1300 to the Spanish invasion) new elements from these same regional metallurgies were introduced, in addition to technical components from the metallurgy of southern Peru. Although the roots of West Mexican metallurgy lay in the metallurgies to the south, the elements that had been introduced from those areas were reinterpreted and transformed, resulting in the development of a technically original, highly inventive regional technology in West Mexico.

No abstract