Encyclopedia of the Incas

Mining and metallurgy formed an integral part of the Inca political economy.
The Incas mined copper, gold, silver, lead, tin, and possibly zinc as well as a
variety of other minerals such as turquoise, obsidian (a volcanic glass), and
cinnabar (an ore of mercury). The objects created from these minerals included
small tools, weapons, and a variety of personal ornaments and ritual items.
While many of these objects had practical uses, all were imbued with social and
religious significance, as were the very acts of mining and smelting. The
practical, political, and ideological were thus intrinsic aspects of the production
of metal and other materials won from the earth.
No systematic survey of the location of mines throughout the Inca realm has
been conducted, but a number of regional surveys have been done. In Peru, Inca
mines and mineral processing sites have been identified on the coast and the
western shores of Lake Titicaca. The most thorough surveys have been
conducted in the mineral-rich southern Andes where archaeologists estimate that
50–80 percent of the Inca sites identified in northwestern Argentina and northern
Chile are associated with mining or metallurgical activities. These figures
indicate not only the intensity of Inca mining, but also suggest that access to
minerals was a primary factor motivating Inca expansion into the region.
The organization of Inca mining was shaped by imperial policies, as well as by
technological requirements and local socioeconomic conditions. Mining and
agriculture were organized in a similar fashion, with the state claiming dominion
over all mineral deposits, but allowing less productive mines to be worked by
local leaders. These provincial rulers were expected to offer silver and gold to
their imperial overlords, and following Andean norms of reciprocity, also
received such gifts from the Inca. The exchange of metal items thus played an
important part in the imperial political economy.
Inca mines were closely supervised by state personnel. Workers included
nearby populations complying with the mit’a, the rotating, state-imposed labor
draft (see Labor Service), and mitmacuna, colonists who were permanently
relocated in order to supply a self-sufficient labor force. Yanacuna, specialized
retainers who worked for the Inca, were probably employed to perform skilled
tasks such as smelting. Workers were often drawn from communities already
familiar with mining, and in all cases, couples, rather than individual men, would
have been recruited by the state.
The Incas took over previously established facilities and constructed new
mining centers in sparsely populated areas; in both cases the way in which
production was organized appears to have been similar. El Abra, a copper and