Published online by Cambridge University Press: 20 January 2017
This paper reports a series of obsidian hydration dates from Temesco, a small Terminal Late Preclassic ceremonial site in the Valley of Mexico. Temesco is located in the Texcoco Plains, an area which may have played a key role in the emergence of the elaborate Classic Period Teotihuacan civilization. Analysis of ceramics and cross-dating with radiocarbon dates from Cuicuilco suggest that Temesco was a short-span site of the first century B.C. Confidence in this conclusion is reinforced by obsidian dates as an independent line of evidence giving approximately the same result.