2.1 A Brief History of MAteriAls
Our species, Homo sapiens, differs from others most significantly,
perhaps, in its ability to design and make things. Making implies
the use of materials. Materials have enabled the advance of mankind
from its earliest beginnings; indeed, the ages of man are named
after the dominant material of the day: the Stone Age, the Copper
Age, the Bronze Age, the Iron Age (Figure 2.1). If you have seen the
movie 2001: A Space Odyssey, you might remember one of the first
scenes, in which prehistoric humans fight using animal bones. It is
known that the tools and weapons of prehistory, 300,000 or more
years ago, were bone and stone. Stones, particularly flint and quartz,
could be shaped for tools; these materials could be flaked to
produce a cutting edge that was harder, sharper, and more durable
than any other material that could be found in nature.
Gold, silver, and copper, the only metals that occur in native form,
must have been known from the earliest times, but the realization
that they were ductile, could be beaten into complex shapes, and,
once beaten, could be hardened seems to have occurred around
5500 BC—almost 300,000 years after the time stone and bone were
first used. By 4000 BC there is evidence that technology to melt
and cast these metals had developed, allowing more intricate
shapes. However, metals in native form, such as copper, are not
abundant. Copper occurs in far greater quantities as the minerals
azurite and malachite. By 3500 BC, kiln furnaces, developed for
pottery, could reach the temperature required for the reduction of
these minerals, making copper sufficiently plentiful to usher in the
Copper Age. But even in the deformed state, copper is not all that
hard. Poor hardness means poor wear resistance; therefore copper
weapons and tools were easily blunted.
17
An Evolutionary Perspective
C HApter 2
Nanomaterials, Nanotechnologies and Design
Copyright 2009 Elsevier Ltd. All rights of reproduction in any form reserved.
Our species, Homo sapiens, differs from others most significantly,
perhaps, in its ability to design and make things. Making implies
the use of materials. Materials have enabled the advance of mankind
from its earliest beginnings; indeed, the ages of man are named
after the dominant material of the day: the Stone Age, the Copper
Age, the Bronze Age, the Iron Age (Figure 2.1). If you have seen the
movie 2001: A Space Odyssey, you might remember one of the first
scenes, in which prehistoric humans fight using animal bones. It is
known that the tools and weapons of prehistory, 300,000 or more
years ago, were bone and stone. Stones, particularly flint and quartz,
could be shaped for tools; these materials could be flaked to
produce a cutting edge that was harder, sharper, and more durable
than any other material that could be found in nature.
Gold, silver, and copper, the only metals that occur in native form,
must have been known from the earliest times, but the realization
that they were ductile, could be beaten into complex shapes, and,
once beaten, could be hardened seems to have occurred around
5500 BC—almost 300,000 years after the time stone and bone were
first used. By 4000 BC there is evidence that technology to melt
and cast these metals had developed, allowing more intricate
shapes. However, metals in native form, such as copper, are not
abundant. Copper occurs in far greater quantities as the minerals
azurite and malachite. By 3500 BC, kiln furnaces, developed for
pottery, could reach the temperature required for the reduction of
these minerals, making copper sufficiently plentiful to usher in the
Copper Age. But even in the deformed state, copper is not all that
hard. Poor hardness means poor wear resistance; therefore copper
weapons and tools were easily blunted.
17
An Evolutionary Perspective
C HApter 2
Nanomaterials, Nanotechnologies and Design
Copyright 2009 Elsevier Ltd. All rights of reproduction in any form reserved.