Silver mining remained of fundamental importance to the Spanish imperial economy in the late colonial period, despite the increased attention paid by the crown to policies of economic diversification. By 1776, when Upper Peru was incorporated in the new viceroyalty of the Río de la Plata, the mining city of Potosí was a shadow of its former self. But it remained the most important mining center in South America, and, together with surrounding provinces, was responsible for over 60 percent of total Peruvian production. Research into the economic history of the new viceroyalty has tended to concentrate upon the development of the more dynamic Buenos Aires rather than of Upper Peru. This meticulous monograph, based upon a wide range of Spanish, Argentine, and Bolivian archival sources, goes some way toward redressing the balance, although its twin concerns are social history and the impact of the Bourbon reforms in Potosí rather than economic life as such. Separate chapters deal with the mainly abortive attempts of visitador Jorge de Escobedo to reform the structure of the mining industry up to 1782, the failure of the Nordenflicht mining mission to modernize the refining process, and the rejection by the crown of Pedro de Cañete’s Mining Code of 1794. The analysis then proceeds to the mid-1790s polemic about the mita system between the intendant Francisco de Paula Sanz and the protector of the Indians Victorián de Villava. One problem with this approach is that themes of fundamental importance—the structure of the labor force, the administration of the industry, even the level of silver production—are considered in the context of these particular crises rather than in a systematic way for the period as a whole. Thus, mercury supply is discussed only in the light of the 1800-1804 silver-production crisis, caused by the suspension of mercury shipments from Spain.

A more thorough analysis is provided of the social composition of the mining guild. It demonstrates the complex links between immigrant silver producers and the creole owners of refining plants, who tended to rent their facilities to the new arrivals rather than engage directly in large-scale production. The internal affairs of the guild, it is shown, were characterized on the one hand by the factious squabbles for which miners throughout the empire were notorious and, on the other, a readiness for all members to combine with local administrators against interference from both Buenos Aires and Madrid. It is perhaps in keeping with this latter trait that the monograph, too, tends to be introspective: only a few passing references are made to the structure and development of the mining industry in neighboring Peru, despite the availability of considerable information as a result of recent research, and, of course, the long historical connection between the two industries. It is noted in the preface that a long (and potentially fascinating) section on Potosí’s role as a commercial center, entrepôt, and stimulator of trade, agriculture, and industry in the area has been omitted for lack of space.