Encyclopedia of Society and Culture in the Ancient World

(Sean Pound) #1

During the fi rst 500 years c.e. the knowledge of how
to mine, smelt, and work iron may have been spread by the
Bantu-speaking peoples of Africa during their great migra-
tions across central Africa. Among them, certain craft s be-
came the specialties of certain clans. An entire village might
have been devoted to the manufacture of iron products.
People probably processed iron mostly outdoors, but they
probably turned iron into tools or other items indoors in huts
similar to ones used for homes. Typically, men smithed the
iron, but it seems women were more likely to trade iron prod-
ucts to other people. Much of the spread of ironworking to
the south of Africa seems traceable to the movements of the
Bantu-speaking peoples.


EGYPT


BY MARIE PASSANANTE


Metallurgy is the science that deals with the procedures used
in extracting metals from their ores, purifying and alloying
metals, and creating useful objects from metals. Th ese pro-
cedures include smelting, casting, and annealing. Smelting
is the melting of ore to extract metal from it. Unfortunately,
there are no references to smelting in Egyptian texts. All the
information we have is from archaeological evidence as well
as from experimentation based on recovered artifacts.
Smelting, a relatively simple process, had been developed
by the Early Dynastic Period (2920–2575 b.c.e.), and it is pos-
sible that the process was used as early as 4000 b.c.e. During
smelting, crushed ore is mixed with charcoal. Th is mixture,
called the charge, is then placed in a crucible or mud brick–
lined furnace and roasted.
Th is procedure reduces the metal to prills—small pel-
lets—embedded in slag, or waste material. Th e prills are ex-
tracted by crushing the slag and then melted together to form
ingots. A simple smelting furnace would consist of a hole in
the ground rimmed with a wall of mud bricks. Holes in the
wall would accommodate tuyeres, or nozzles through which
air is delivered into the furnace. Blowpipes or bellows would
introduce air into the tuyeres. Blowpipes are represented in
tomb reliefs as early as the Fift h Dynasty (2465–2323 b.c.e.).
Pot bellows were probably in use as early as the Middle King-
dom (2040–1640 b.c.e.), but there is no direct evidence of
their use before the Eighteenth Dynasty (1550–1307 b.c.e.).
Pot bellows consist of a pottery nozzle, a piece of leather cov-
ering the wide end. Th e leather would be squeezed either by
hand or by foot, driving air into the connecting tuyere.
Casting is the process by which an object is created by
pouring molten metal into a mold. Cast objects have been
dated as early as the Predynastic Period (4000–3000 b.c.e.).
Th e process is depicted in the reliefs in the tomb of the Eigh-
teenth Dynasty vizier Rekhmire (ca. 1450 b.c.e.). In these re-
liefs metalworkers are creating a pair of bronze doors for the
shrine of Amun in Karnak. Th e molten bronze is contained
in a crucible (a vessel used to melt or heat metal), which is
handled by two men using wooden sticks as tongs. Th e men


pour the liquid bronze into series of funnels inserted into the
mold; the multiple funnels ensure the even distribution of
metal. Th e crucible containing the metal is bowl shaped and
has a hole in the side for pouring. A mold could be carved in
stone, shaped in pottery, or even formed in sand.
Th e lost-wax method of casting allowed the craft sman to
fashion an object with greater detail, and for this reason it was
a favored method for creating fi gurines and amulets. First the
craft sman sculpted in wax a model of the desired object. He
then covered the wax model in clay and fi red the result. Th e
heat hardened the clay to create the mold and melt the wax,
leaving a space into which the molten metal would be poured.
Aft er the metal had cooled, the mold was broken to extract the
casting. Alternatively, the craft sman could use a modifi ed ver-
sion of the lost-wax method called hollow casting. Instead of
modeling a fi gure wholly out of wax, he would model the wax
around a clay core. Th is model would be covered in clay and
fi red just as in the lost-wax method. Th e core would be held in
place by iron struts, which were in use by the Th ird Intermedi-
ate Period (1070–712 b.c.e.), or possibly by pure copper struts.
Hollow casting was favored in the production of larger objects
because less metal was used and because the process reduced
potential shrinkage and distortion in the mold.
In annealing, a piece of worked metal is heated to reduce
the hardness and brittleness that result from hammering.
Th e heat rearranges the internal structure of the metal, mak-
ing it easier to shape. Th e earliest object showing evidence
of annealing is a copper ax head from the Naqada II Period
(3500–3000 b.c.e.). Th ere are few textual references to an-
nealing. Th e captions in the metalwork ing scenes in two Fift h
Dynasty tombs mention heating sheet metal aft er hammer-
ing it. In the tomb of Wepemnofret, the caption states that the
reason for heating the metal is to reduce chance of cracking
and imperfections, the very defi nition of annealing.
Copper was made into a wide range of objects, from tools
a nd we ap on s to s t at ue s , b ot h a s pu re c opp er a nd i n a l loy s w it h
arsenic, tin (bronze), and lead. Th e earliest examples of cast
copper date from the Naqada Period (3300–3000 b.c.e.), and
lost-wax casting was in use by the Old Kingdom (2575–2134
b.c.e.). Copper statuary is rare before the Middle Kingdom,
and production peaks only in the Th ird Intermediate Period.
Gold is perhaps the easiest metal to work, and it did not
need to be smelted. Gold was extracted from the earth by
placing gold-bearing sand or crushed rock in a vessel with
water and agitating the mixture to separate the particles;
gold is heavier and sinks to the bottom, while the sand and
crushed rock are discarded with the water. Gold was not re-
fi ned further until the Late Period (712–332 b.c.e.), despite
having been in use since the Predynastic Period. Gold was
worked both by casting and by cutting and shaping sheet gold
(gold hammered into a thin sheet). However, because cast-
ing wasted metal, objects made from sheet gold outnumbered
cast objects; most jewelry and amulets were made from sheet
gold, and objects that were cast oft en had components made
from sheet gold.

metallurgy: Egypt 679
Free download pdf