Th e goldsmiths of southwestern Colombia achieved a
high level of excellence with lost-wax casting. Th ey were able
to take advantage of a lower melting point with the higher
copper content, much better suited for casting. Artisans be-
gan by carving a rough semblance of the image in the core,
made up of a mix of clay and pulverized charcoal. Th is core
(or several cores or molds) was fi lled or lined with beeswax.
When there were various parts in beeswax, they were joined
together with small pegs. Th e entire assembly was then placed
in an outer mold of clay and charcoal, pierced with holes. Th e
gold was melted in a crucible and poured into the holes in the
outer mold, melting away the wax. Th e mold was broken open
to reveal the gold object.
Th ere are indications that Colombian goldsmiths were
capable of depletion gilding, a technique that produced a
seamless surface layer of gold. Th e object was formed of
tumbaga, a gold-copper alloy, with a high (60 percent) cop-
per content. Goldsmiths removed the surface copper by
heating the piece in an open hearth until the copper oxi-
dized. Th e black oxidized copper was dissolved from the
surface with a plant-based acid solution, leaving behind a
thin layer of almost pure gold that could be burnished to a
high fi nish.
See also adornment; agriculture; art; ceramics and
pottery; crafts; death and burial practices; econo-
my; gender structures and roles; inventions; migra-
tion and population movements; mining, quarrying,
and salt making; money and coinage; settlement pat-
terns; trade and exchange; war and conquest; weap-
onry and armor.
FURTHER READING
D. Brown, “Bronze and Pewter,” in Roman Craft s, ed. D. Strong and
D. Brown (New York: New York University Press, 1976).
S. A. Butcher, “Enameling,” in Roman Craft s, ed. D. Strong and D.
Brown (New York: New York University Press, 1976).
P. T. Craddock and M. J. Hughes, eds., Furnaces and Smelting Tech-
nology in Antiquity (London: British Museum, 1985).
B. M. Fagan, Th e Seventy Great Inventions of the Ancient World
(London: Th ames and Hudson, 2004).
Michele Feder-Nadoff , ed., Ritmo del Fuego/Rhythm of Fire: Th e
Art and Artisans of Santa Clara del Cobre, Michoacan, Mexico
(Chicago: Cuentos Foundation, 2004).
Robert J. Forbes, Studies in Ancient Technology, 3rd ed. (Leiden,
Netherlands: Brill, 1993).
Herbert Garland, Ancient Egyptian Metallurgy (London: Charles
Griffi n, 1927).
Ian Glover, P. Suchitta, and J. Villiers, eds., Early Metallurgy, Trade
and Urban Centres in Th ailand and Southeast Asia (Bangkok,
Th ailand: White Lotus, 1992).
J. F. Healy, Mining and Metallurgy in the Greek and Roman World
(Ithaca, N.Y.: Cornell University Press, 1978).
J. W. Humphrey, J. P. Oleson, and A. N. Sherwood. Greek and Ro-
man Technology: A Sourcebook (London and New York: Rout-
ledge, 1998).
George Kuwayama, ed., Th e Great Bronze Age of China: A Sympo-
sium (Seattle: University of Washington Press, 1983).
H. Lechtman and A. Steinberg, “Bronze Joining: A Study in Ancient
Technology,” in Art and Technology: A Symposium on Classical
Bronzes, ed. S. Doeringer, D.G. Mitten, and A. Steinberg (Cam-
bridge, Mass.: MIT Press, 1970).
Jian Leng, Early Paleolithic Technology in Eastern and Southern Asia
(Oxford, U.K.: J. and E. Hedges, 2001).
Alfred Lucas, Ancient Egyptian Materials and Industries, 4th rev.
ed. (London: Edward Arnold Publishers, 1962).
C. C. Mattusch, Classical Bronzes: Th e Art and Craft of Greek and
Roman Statuary (Ithaca, N.Y.: Cornell University Press, 1996).
Colin McEwan, ed., Pre-Columbian Gold: Technology, Style, and
Iconography (London: British Museum Press, 2000).
Jean-Pierre Mohen and Christiane Eluère, Th e Bronze Age in Eu-
rope, trans. David Baker and Dorie Baker (New York: Harry
N. Abrams, 2000).
Paul T. Nicholson and Ian Shaw, eds., Ancient Egyptian Materi-
als and Technology (Cambridge, U.K.: Cambridge University
Press, 2000).
Ray Smith, “Ray Smith’s Notebook of Metalworking Origins.” Avail-
able online. URL: http://www.anvilfi re.com/21centbs/stories/
rsmith/RSindex.htm. Downloaded on February 20, 2007.
Rebecca Stone-Miller, Art of the Andes: From Chavín to Inca, 2nd
ed. (London: Th ames and Hudson, 2002).
Trevor I. Williams, Th e History of Invention: From Stone Axes to
Silicon Chips (New York: Facts On File, 1987).▶ migration and population
movementsintroduction
In a broad sense, the history of human migrations is the his-
tory of two profound desires: the desire to have a place that
is home and the desire to live a better life. Th ese desires have
manifested themselves in settlements and movements for
thousands of years. At present most anthropologists believe
that the ancestors of the modern human being developed in
eastern Africa, during a period when the land was dry and
resources for survival were few. Some of these fi rst human
beings migrated south in Africa, others west in Africa, and
others remained in eastern Africa.
What motivated human beings to leave eastern Africa
is not known, but the hostility of the climate may have had
something to do with it. People may have left to fi nd better
sources of game and edible plants. Some people moved north-
ward, perhaps following game, and they may have followed
game, perhaps migratory animals, out of Africa and into the
Near East. Th ey may not have realized that they were doing
anything exceptional; they would just have been providing
themselves and their families with food from wherever they
could fi nd it.
It is worth remembering that the people who migrated
throughout the world in ancient times probably had motiva-
tions similar to those of modern people, and their reasons688 metallurgy: further reading