Obsidian in Southern Ecuador: The Carboncillo Source

Resumen

Abstract The Carboncillo area in the southern highlands of Ecuador is identified as the only confirmed source of archaeological obsidian located in the country outside of the northern highlands and is the first identified in the large gap between the known Ecuadorian and Peruvian sources. With the identification of this source, it can no longer be assumed that all obsidian found in Ecuador came from sources in the northern highlands. Thus the Carboncillo source has significant implications for interpreting patterns of long-distance exchange in the Andes, especially in southern Ecuador and the far north of Peru. A geochemical analysis of the Carboncillo material shows that it can be easily distinguished from the obsidian from other Ecuadorian sources. A provenance study of archaeological obsidian samples from the southern highlands of Ecuador using x-ray fluorescence demonstrates that the Carboncillo obsidian was used at the Preceramic site of Chobshi Cave and at a number of late prehispanic sites in the Saraguro region. The results indicate a high level of sociopolitical and economic isolation in late prehistory, most likely tied to a preoccupation with warfare between neighboring groups, and provide additional evidence that the economic organization of the southern highlands differed markedly from that of the north during this time.