Silver mining was one of the primary sources of income from the Americas for the Spanish circa the 15-18th centuries CE. (time period) Though many conquistadors and explorers originally went to the Americas looking for gold, silver was much more valuable and abundant and eventually became the focus of much of the Spanish American enterprise. Silver production was mostly in the Mexican north and the central Andes and as a result, large numbers of indigenous peoples were deployed there as laborers. Some were voluntary workers (due to pressures from conquest and disease) and others were forced. The discovery of the huge deposits of silver in the Andes created a boomtown, with a population by 1600 of over 150,000. (explanation)The high rate of death among the laborers however, influenced additional distribution of the population, as many indigenous workers fled to live in the growing cities. (impact, significance)The silver mining industry powered the Spanish economy and stimulated the world economy of modern times. American silver was traded in Asia and Africa, enabled Europeans to purchase silks and spices, helped create a powerful army and bureaucracy in Spain and helped European and the larger world economies establish new and stronger links between Asia and the Americas. Silver helped to start the global economy and set a foundation for more European power in the world.(significance)