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Gold

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GENERAL

Gold has a very special place in human history. It has been treasured since ancient times and was the first metal used by humans, with simple gold ornaments among the earliest known metal objects. In early times, alchemists would spend their entire lives trying to turn other metals into precious gold! Gold has changed where and how people live. Many towns have been developed by the wealth from mining gold. There are also many ‘ghost towns’ - when the gold supply ran out, people simply deserted the area.

Gold has also featured in many myths and legends. King Midas, King Soloman, and Jason and the Argonauts were all legendary gold seekers! Even fairytales often mention golden objects such as eggs or harps, and most people have heard of the golden pot at the end of the rainbow. Even today, achievements are rewarded by gold medals, and we associate the word gold with greatness - as in ‘golden rules’ or ‘good as gold’. Gold has always been, and still is, a very important metal. Its rarity and unique properties make it one of the most prized and useful metals.

PROPERTIES

  • Gold is the only yellow metal, and it is usually found in nature as a native metal.
  • Gold is shiny and will not rust or stain.
  • Gold conducts electricity and has a high melting point.
  • Gold is about 19 times heavier than water which means it is nearly twice as dense as lead.
  • Gold is malleable and ductile - one ounce can be beaten into a see-through thin sheet of nine square metres or drawn out into a wire 80 kilometres long!
  • Gold has the symbol Au.
  • Gold is soft and scratches easily.
  • Gold can be recycled mostly into jewellery and electronic components.

USE DESCRIPTION
Money Gold has been used as coins since early times, but very few coins are made from gold today. More than half the world’s gold is stored by governments and banks. One kilogram of gold is worth about $15 000, although the price of gold varies from day to day.
Jewellery Although pure gold (24 carat gold) is rarely used as it is too soft, gold is often mixed (alloyed) with other metals such as copper, silver or nickel for jewellery (18 carat gold means 18 parts gold and 6 parts other metals).
Decoration As gold can be rolled very thin and is durable, it’s often used to coat metal or glass objects. Small sheets of ‘gold leaf’ are also often used for decorative letters, gilding book edges and picture frames, and to coat religious statues.
Electronics As it conducts electricity and is ductile, gold is used for wiring in computers - from digital radios to microwaves, from telephone systems to rocket launchers! Gold is very useful for wiring that is difficult to repair, such as under water and in outer space, because it does not corrode or wear out quickly.
Shielding Rays of light do not easily pass through gold so it is useful as a protective shield against heat and light. Buildings in tropical countries sometimes have a transparent film of gold on the windows. Jet engines, space suits and space craft are often coated in gold to reduce heat and glare.
Health Gold is used to replace or repair teeth and in the treatment of arthritis and other diseases. Lasers in industry and medicine use gold-coated reflectors to focus light energy.

SOURCE

Large pieces of gold are called nuggets, and tiny pieces are known as gold dust. Sometimes, where weather has worn away rocks, gold is left exposed on the surface and can be washed into creeks and rivers to form ‘alluvial deposits’. In the past, many prospectors found gold by panning the gravel of river beds for the heavy gold which falls to the bottom; but it is much harder to find that way today.

Mostly, gold is spread throughout the rocks and soil around us but in such low amounts that it’s not worthwhile trying to get it out. However, there are some places where there is enough gold to mine. Australia (especially Western Australia) is the world’s third-biggest producer of gold, with both open-cut and underground gold mines.

The gold-bearing rock is first blasted and dug out (about two hundred tonnes of ore has to be mined to produce just one kilogram of gold), then crushed, and the powder is mixed with water. The gold sinks and the other wastes are washed away. The gold is treated with chemicals, melted and further purified, in a process called ‘smelting’. It is then poured into moulds where it cools and hardens as gold bars called ‘bullion’, which make the gold easy to stack and transport.

 

AMAZING FACTS

Long ago, in 5000 BC, the Egyptians found gold in the bed of the Nile River, and for thousands of years used gold for objects of adornment. When King Tutankhamen died, his mummified body was partly covered with gold which looked just as shiny when it was discovered by archaelogists over 3000 years later!

Christopher Columbus was in search of gold when he discovered America in the 15th century.

The earliest recorded gold sighting in Australia was in NSW in 1823. In 1851 the first of our ‘gold rushes’ began, gold fever enticing people to Victoria from many parts of the world. Within 10 years, Australia’s population trebled, to more than 1 million people.

In 1854, gold miners angry at the unfair miner’s licence system, fought against troopers in the famous Eureka Stockade battle, the only armed rebellion in Australia’s history.

The largest gold nugget ever found was the ‘Welcome Stranger’, found in 1869 just under the soil at the base of a tree! It weighed 70 kg and on today’s value would be worth over 1 million dollars. Quite a find!

The term ‘digger’, the nickname for Australian soldiers fighting overseas, comes from the fact that many of the World War I soldiers had literally been diggers in the goldfields just before the war.

OPERATING GOLD MINES