Over the course of the eighteenth century, annual silver production in Mexico quadrupled, due in large part to cheaper and more abundant supplies of mercury, a key ingredient in the refining process. Nearly all mercury used by Mexicans during the eighteenth century came from Almadén, the royal quicksilver mines in southern Spain, where output increased more than tenfold over the 1700s.

Thus, the second volume of Antonio Matilla Tascón’s history of the Almadén mines is important not only to students of Spanish history but also as a key source for those interested in Spanish American mining. It picks up the story of Almadén in 1646 (volume I traced their history to 1645), when the Spanish crown resumed control from the Fuggers and began direct operation of the mercury mines. Drawing almost exclusively on Spanish arehival materials related to Almadén, Matilla describes in detail the administrative and technological reforms carried out by the Bourbons to cut production costs and expand output. Individual chapters describe the mines and the personnel, including prisoners and slaves, who extracted and refined ore; trace the activities of the various governors and administrators; sketch the government’s successful attempts to raise the technological level of operations, in part through use of foreign expertise; and provide data on the distribution of mercury.

Because the volume is primarily descriptive rather than analytical and focuses narrowly on Almadén, it ignores broader issues related to mining and Bourbon policy. The government’s activities at Almadén constitute one of the Bourbons’ major economic achievements, due to both fortuitous discovery of new mines and adroit administration, yet Matilla provides no analysis of how developments at Almadén fit into the broader context of Bourbon state building. Similarly, Spanish American silver refiners comprised the chief market for the vast expansion in output at Almadén, but this study offers no discussion or explanation of the relationship between Almadén and its New World markets. Still, its rich detail offers many insights into such issues, and this long-awaited hook will be much consulted by students of Spanish American mining.