![]() ![]() The most common gold compounds are auric chloride (AuCl 3) and chlorauric acid (HAuCl 4). Gold is readily available commercially and its price changes day by day and is one of the most widely tracked commercial prices. It is a good conductor of heat and electricity, and is unaffected by air and most reagents. It is a soft metal and is usually alloyed to give it more strength. It is the most malleable and ductile metal 1 ounce (28 g) of gold can be beaten out to 300 square feet. It is metallic, with a yellow colour when in a mass, but when finely divided it may be black, ruby, or purple. It is estimated that all the gold in the world, so far refined, could be placed in a single cube 60 ft. Gold is usually alloyed in jewellery to give it more strength, and the term carat describes the amount of gold present (24 carats is pure gold). Remarkably other colours such as purple (a gold:aluminium alloy), blue (a gold:indium alloy) and even black (a gold:cobalt alloy) may be formed. Addition of some copper gives "rose gold", a soft pink colour. White gold is commonly used for wedding rings in the USA. White gold for jewellery is formed by mixing palladium, silver, or nickel with gold, although the result is green gold with certain proportions of silver. Small amounts of other metals alloyed with gold change the colour as well as mechanical properties such as hardness. The gold colour seems related to relativistic effects of the outermost gold orbitals. Gold can be found freely in nature, however it is usually found in silver, quartz, lead, zinc or copper.Most metals are metallic grey or silvery white whereas gold is characteristically a metallic yellow colour, in other words gold-coloured. Gold is used to symbolise purity, value and royalty. ![]() History of Gold Since prehistoric times, gold has been known about and highly valued. If this amount of was distributed to every person in the world, you would have only about 23 grams of gold.This is the amount of of gold that has been produced. Imagine a solid gold cube about the size of a tennis court.There is about 120,000 to 140,000 tonnes of gold above ground.In every ton of seawater 1 milligram of gold has been dissolved, but at the moment it currently costs more to extract the gold from this than what the gold is worth itself. Or The fact that gold is so malleable and ductile one gram of it can be beaten into a one square metre sheet. The properties of gold give it the ability to be beaten into sheets no thicker than 0.00001 mm or 400 times thinner than a human hair. ![]() Some of the greatest treasures of goldsmiths art was also found in his tomb.
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