Although the element copper ranks only 26th in abundance in the earth's crust, far below a host of metals such as aluminum, iron, calcium, sodium, potassium, magnesium, and titanium, copper is one of the few naturally occurring metals in nature that can be used directly.
The use of copper by humans was recorded as early as around 8000 BC. Thousands of years later, copper was the first metal to be smelted (about 5000 BC); the first to be cast in molds (about 4000 BC); and the first to be alloyed (about 3500 BC).
From the Stone Age
Before the advent of copper, humans had developed and become proficient with a variety of stone tools. It was through the pounding and shaping of copper by stone tools that man's exploitation of copper began. Due to the low hardness of pure copper, no high temperature smelting was required to allow primitive man to mechanically process copper.
After repeated pounding, the stone tools may have crumbled, but the copper remained intact because of its excellent ductility. As a result, copper could be used to make fishhooks, needles, scythes, and a variety of other fine and complex tools. Not only are these tools lighter and more durable, but they can also be recycled even when they wear out.
Copper's unique metallic luster also made it ideal for use in making decorative and ceremonial objects, which became symbols of status or religious rituals. The use of copper enabled mankind to leapfrog in productivity and culture, and thus ushered in a new era of civilization.
Bronze Age
Bronze was invented as people processed copper more deeply. Bronze is an alloy of copper and tin, which is harder, stronger and more resistant to corrosion than pure copper, and therefore tools and weapons made of bronze are more durable.
As the most sophisticated material of the time, bronze was widely used in various fields such as military (weapons and defense equipment), culture (ceremonial objects), and economy (money), and became synonymous with an era.
The Age of Electricity
With the spread of electricity, copper once again shone because of its good electrical conductivity, thermal conductivity, ductility, and malleability, and was used in a large number of wires, cables, pipes, radiators, integrated circuits, and a variety of electrical equipment, and the demand for copper is therefore considered to be a barometer of the world's economy.
