The Spanish conquest of Peru was motivated by the quest for precious metals, a search that resulted in the discovery of massive silver deposits in what is now southern Bolivia. The enormous flow of specie into the world economy is usually attributed to the Spanish imposition of a forced labor system on the Indigenous population as well as the introduction of European technology. This narrative omits the role played by thousands of independent miners, often working illegally, who at different points in history generated up to 30 percent of the silver produced in the region. In this work, Mary Van Buren examines the long-term history of these workers, the technology they used, and their relationship to successive large-scale mining.

The methods of historian Bertell Ollman, particularly a dialectical approach and "doing history backwards," are used to examine small-scale mineral production in Porco, Bolivia. The research is based on nine seasons of archaeological fieldwork and historical research, with a particular focus on labor and technology. Van Buren argues that artisanal mineral production must be understood in relation to large-scale mining rather than as a traditional practice and that the Bolivian case is a culturally specific instantiation of a broader economic phenomenon that began under colonial regimes.