Alvaro Alonso Barba, Arte de los Metales. Lima, 1640.
The search for precious metals was centrally important from the earliest moments of Spanish contact with the New World. In South America, the silver mountain of Potosí became synonymous with enormous wealth. “Vale un Potosí,” “It’s worth a Potosí,” became a common phrase. But soon after the Spanish began exploiting it, in large part with forced Indian labor, surface deposits and easily smelted ores were depleted, even with the sophisticated indigenous smelters known as huayra. In mid-sixteenth-century Mexico, Bartolomé de Medina perfected the process of extracting silver from ore by way of mercury amalgamation, known as the “patio process.” The process quickly became the dominant means of producing silver, and substantially increased yields. Barba’s treatise on mining was first published in 1639, and was the result of over twenty years of study of mining practices in Peru, including additional refinements to the patio process. It quickly saw republication, and was translated into English as early as 1670.