Did you know? Gold facts:
• Gold’s chemical symbol is AU. It comes from the Latin word “Aurum” which means shining dawn.
• Gold is resistant to corrosion. It will never rust
• An ounce of gold can be hammered into a 100 square foot sheet
• Gold is measured in troy ounces which is heavier than the standard ounce. 1 troy ounce = 31.103grams
• Gold is completely recyclable
• Gold is the most ductile and malleable of all the metals. One ounce can be drawn into a wire that stretches five miles
Gold is a very rare substance making up only five ten-millionths of the Earth's outer layer.
(Imagine 10 million coins in one place and only 5 of them were made of gold!).
Its rarity and its physical properties have made it one of the most prized of Earth's natural resources.
Gold, like iron, copper, lead, etc. is a metal. Metals are good conductors of heat and electricity and are almost all solid at room temperature (with the exception of mercury). They are malleable and ductile.
Chemical Symbol: Au
Name Origin: From the Old English word geolo (yellow) 
Symbol Origin: From the Latin word aurum (gold)
Date of Discovery: circa 3000 BC
Discoverer: Unknown
Atomic Number: 79
Atomic Mass: 196.96655 amu
Melting Point: 1064.43 °C (1337.5801 K, 1947.9741 °F)
Boiling Point: 2807.0 °C (3080.15 K, 5084.6 °F)
Relative Density: 19.3
Hardness: 2.5-3 on Mohs scale
Malleability: High
Ductility: High
Gold is heavy — it weighs over nineteen times more than water, and is almost twice as heavy as lead.
If you had enough Gold to fill a one litre milk carton, it would weigh 19.3 kilograms, the same volume of milk weighs only one kilogram.
Gold is quite soft. It is slightly harder than a fingernail but not as hard as a coin or glass.
Gold, like most metals, can be hammered into thin sheets or drawn out into thin wires.
This has made gold sought after for a wide range of applications, like jewellery and in electronics.
"Gold leaf" for example, is gold that has been beaten into a sheet less than one tenth of a millimetre thick.
It is then used for lettering on honour rolls in schools, or for putting gold onto picture frames and ornaments.
Gold is chemically very stable. It does not readily combine with other substances and, therefore, does not corrode or tarnish. Because of this property, it is found in nature almost always as pure gold. This is referred to as "native gold".
This meant that the early humans could collect the gold and use it without having to smelt or refine the metal from a mineral — such is the case of iron.
Also, because Gold is soft and does not tarnish or corrode, it makes excellent jewellery, it is good as material for filling cavities in teeth, and it makes excellent fine wire for electronics.
Gold is very reflective, so it is used to protect spacecraft and satellites from solar radiation.
Industrial and medical lasers use gold-coated reflectors to focus light energy.
If you were made of Gold, how much would you be worth? Click on the link to find out http://www.ga.gov.au/education/minerals/calculator/calculator.html
A Troy ounce is 480 grains, somewhat heavier than an avoirdupois ounce (437.5 grains).
A grain is exactly 64.798 91 mg; hence one troy ounce is exactly 31.1034768 g, about 10 percent more than the avoirdupois ounce, which is exactly 28.349523125 g. The troy ounce is the only ounce used in the pricing of precious metals, such as gold, platinum and silver.
The troy grain is used to measure bullet and gunpowder weights in shooting and arrow and arrowhead weights in archery. In troy weight, there are 12 ounces in a pound, rather than 16 as in the more common avoirdupois system. The troy ounce may be abbreviated to ozt.
The troy system of weight is named after the city of Troyes in France, and was widely used in Europe during the Middle Ages. It fell into disuse when other systems began to be preferred, continuing to be used only in the highly specialised fields of precious metals, gems and medicines, up to the nineteenth century. Today it is only used for the trading of precious metals and gemstones.
1 troy ounce = 0.0311 kilograms
32.1507 troy oz = 1 kilogram
1 troy ounce = 31.1034768 grams