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GENERALEvery time you switch on a light, use an appliance in your home, or turn on a tap, it is copper that is delivering the electricity or water to you. Copper is therefore a very important metal to humans, and combines more useful properties than probably any other metal!
PROPERTIES
SOURCEAlthough it can be found in its pure form, copper is generally locked together with other minerals such as gold, lead, zinc and silver. A mixture of copper, iron and sulphur is called chalcopyrite or ‘fool’s gold’, and tricked many an old-time prospector! In Australia, the search for copper began soon after European settlement. By the 1860s, South Australia was known as the ‘Copper Kingdom’ because it had some of the largest copper mines in the world. Australia is the world’s fifth largest producer of copper. We have several copper mines which are of world significance, including Mt Isa in Queensland (our largest copper producer) and Olympic Dam in South Australia which is mining out one of the largest copper-bearing ores in the world. Here, copper-bearing rock (ore) is blasted underground, scooped up by front-end loaders, taken in large trucks to underground crushers, then hoisted to the surface in skips up one of the shafts. At the surface, the ore is crushed further, mixed with water and other special chemicals to remove the waste rock and float the copper ore so it can be skimmed off, then heated and treated in other ways to purify the copper and separate it from any other metals.
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AMAZING FACTS A copper pendant dated at 8700 BC was discovered in what is now northern Iraq. A piece of copper tubing from 5000 years ago was unearthed by archaeologists from the Pyramid of Cheops in Egypt. The sixth wonder of the world was the Colossus of Rhodes, a huge statue of Helios the sun-god, made of bronze reinforced with iron and weighted with stones. Another famous bronze artefact is the 15th century pair of baptistry doors in Florence, Italy, hand-sculptured by Ghiberti. In the past, copper’s ability to be beaten into sheets and its resistance to rusting made it popular for roofing on important buildings. In 1837 Charles Wheatstone and William Cooke patented the first electric telegraph, using copper wire. The first major discovery of copper in Australia was at Kapunda in South Australia in 1842 when Francis Dutton found copper ore whilst searching for lost sheep! In 1876 Alexander Graham Bell was the first to use copper telephone wire. In 1878 Thomas Edison invented the first electric light, relying on copper to carry the current to it. Within a few years, the mass use of these two inventions caused an incredible increase in the mining and production of copper. Copper and brass are easily recycled - perhaps 70% of the copper now in use has been recycled at least once. In the future, copper will be used in powder form in super-conductors, and as a coating for coaxial fibre optic cables. It is also bound to be used more and more in maintaining our health and those of our crops and livestock. An average family home contains more than 90 kilograms of copper: 40 kg of electrical wire, 30 kg of plumbing, 15 kg of builders hardware, 9 kg inside electrical appliances, and 5 kg of brass goods. A Boeing 747-200 jet plane contains about 1.8 tonnes of copper. The Statue of Liberty in New York contains more than 37,000 tonnes of copper. |
In fact, copper was the first metal used by our ancestors, discovered by Neolithic Man about 9000 years ago and used in place of stone, as it was far easier to shape! Early coppersmiths in Iran found that heating copper softened it and hammering copper made it harder. In this way, they could shape copper into various useful items such as containers and utensils, a big leap forward for the human race. Because of its beautiful colour, copper was also made into jewellery and ornaments. Around 4000 BC bronze, an even harder alloy, was discovered by mixing copper with a small amount of tin. It was used to make not only decorations but also weapons, armour and tools - thus began the Copper-Bronze Age.
