Drawing on a survey of the Quebrada de Tarapacá in northern Chile and excavations at the Inka and Colonial administrative site of Tarapacá Viejo, we present archaeological evidence of small-scale purification of silver using lead. We argue that the use of techniques to refine silver-bearing ores most likely began in the Late Horizon (AD 1450-1532), when local metallurgists may have processed minerals from the nearby silver mines of Huantajaya as part of their labor tribute to the Inka state. Although the adoption of mercury amalgamation technologies introduced by Europeans allowed for large-scale refining of silver, lead purification techniques continued in use into the early Colonial Period (AD 1532-1700).