Chemistry Reference
In-Depth Information
FIGURE 38
Lead coffin.
Lead coffin (first-third centuries
C
.
E
.) from Jerusalem, Israel.
Lead, widely used in many ancient civilizations, was one of the first metals to be recov-
ered from its ores. Lead objects date back from as early as the seventh century
B
.
C
.
E
.
In Mesopotamia molten lead was used to fasten bolts and shafts into masonry. In Syria
it was made into rods used as currency, and in Greece it was cast into coins. During
the Roman Empire the use of lead become so widespread that the health hazards
caused by lead exposure are suspected to have been one of the factors affecting the
fall of the Roman Empire. Since it is very resistant to corrosion, lead was also used by
the Romans, for making coffins as the one illustrated.
slowly, at room temperature. Because of this flow, sheets of lead in ancient
slanting roofs often develop, over long periods of time, a lower edge much
thicker than at the top. In addition to its use as a metal, a great part of the
lead produced in antiquity was mixed with other metals to make alloys such
as
pewter
and
soft solders
.
Pewter
, an alloy of tin, lead, and some other metals,
was used to make a wide range of utilitarian and decorative objects. Other
lead alloys served for minting coins and sculpting statuary.
The ancient Egyptians used lead as early as the fourth millennium B.C.E.
Later, the Romans developed and expanded the use of lead during the
Roman Empire to impressive levels, so lead is often referred to as the
Roman
metal
. The large-scale use of the metal most probably caused considerable
environmental contamination of food, drink, and the atmosphere (Nriagu
1983).
Tin
Tin
(chemical symbol Sn, from the Latin name of the metal,
stannum
) occurs
as a native metal only as small, rare nuggets; it is very doubtful, therefore,
whether native tin would have been noticed, never mind used, by ancient
people. Nevertheless, tin was one of the earliest metals to have been pro-
duced. Tin ores occur in few places on the upper crust of the earth, mostly
as the mineral
cassiterite
or
tin stone
(composed of tin oxide) from which
most tin has been and still is extracted.
Tin stone
is a usually brown or black,
