Copper: properties, uses, and applications

Copper is perhaps one of the most important elements for mankind, both due to its multiple uses and to its capacity to replace iron in many cases. Starting with making objects out of copper and continuing, as mankind progressed, with its use as a conductor and building material, copper was part of everyday life ever since the copper age. Even today, despite new discoveries that brought about artificially made compounds and alloys, copper remains an important element still significantly used in practice.

Copper is generally found in different minerals, such as bornite and chalcocite, but especially in its oxide form, as a cuprite. Its accessibility in the ground and ease of use, combined with its numerous mechanical and electrical properties (the second highest electrical conductivity after silver, large charge density etc.), made it preferred ever since the early days of mankind.

It is not difficult to trace the use of copper, as copper objects were discovered and accurately dated. Apparently, the use of copper can be traced as far back as 10,000 years BC, although the discovery of a copper pendant in Mesopotamia, dated around 8,700 BC, means that this timeframe is safer to point as the period when copper initially began to be used by mankind. With 5,000 BC, one can already notice copper being smelt, which was obviously an advancement, making production easier and the diversity of objects that could be made larger.

The bronze age, starting around 3,000 BC, brought copper even more into people's lives. Bronze is an alloy which is made primarily of copper and a secondary element, usually tin. The main characteristic of the bronze age was that almost all objects from this period of time were made of bronze. However, sometimes copper was simply not mixed with other elements and was used in its original form. Discoveries of bronze made objects, including in Europe, by the year 2,000 BC, abound.

As the activities of mankind diversified in antiquity, copper began to have new uses as well. One of the important ones was its use as a source for currency making. In the beginning, as an alternative to gold, copper was used in lumps. However, it soon began to be molded in what looked more like the coins we are accustomed to today. It became a form of prestige to make your coins as an emperor, like Julius Caesar started to in the 1st century BC. This trend continued in the Middle Ages, despite the fact that, especially during the first centuries of this historical period, people had reverted to autarchy and trade was almost non-existent. Even today, some of the U.S. coins (dimes, nickels and quarters), for example, are made of copper on the inside, with an outer layer of copper-nickel alloy.

At the same time, copper, usually in its bronze form, had an important use as an element of art in Antiquity. Even today statues of the Roman emperors, made from bronze, can be admired in the museums of Rome. This trend continued 1,000 years later, in the Renaissance period. Artists like Donatello used bronze to cast their statues. Even earlier than that, copper and bronze had been used for the doors of churches and baptisteries, as is the wonderful example of the Baptistery of Florence.

Again, diversification of man's activities implied new uses for copper. Ships were protected from the water erosion, as well as from potential rocks and other obstacles, with copper used on their hulls. With the discovery of electricity and its main laws, copper began to be used extensively as an excellent conductor, a use still valid today in many parts of the world.