Archaeological research carried out in the altiplano locale of Escaramayu (in the community of Escara, Potosí, Bolivia), revealed a prehispanic metallurgical establishment (ninth to fifteenth centuries AD) for the extractive processing of copper ores and, to a lesser extent, lead-silver ore exploited at the nearby Pulacayo mine. The number and variety of metallurgical equipment identified in this establishment for smelting metallic ore and for refining the metal indicate a deep level of technological experience and experimentation among the resident Escaramayu metalworkers during the Middle Horizon (MH) and Late Intermediate periods (LIP). In Escaramayu we find the first known antecedents of Andean wind furnaces (wayras) and a model of a prehispanic reverberatory furnace that was widely used in the southern Andean altiplano during the colonial period.