Home/Bullion/About Bullion

Importance of Gold

What is gold and why is gold so important?

Gold is a rare metal. It has the chemical symbol Au, named after Aurora, the Roman goddess of the dawn. The purity of gold is described by its ‘fineness’ in parts per 1,000 or by the carat scale which is parts per 24. The word ‘carat’ derives from the Italian carato, Arabic qirat or Greek keration, all meaning the fruit of the carob tree. Ancient traders used carob seeds as the means to balance the scales in oriental bazaars. Pure gold is 24 carat or 1,000 fine.

The price of gold and other precious metals is quoted in terms of troy ounces. The term ‘troy’ is derived from Troyes, France, a major trading city of the Middle Ages. One troy ounce equals 31.1 grams.

 

Chemical properties of gold

Chemical Properties Au
Atomic number 79
Atomic weight 196.967
Melting point 1,064 degrees C
Specific gravity 19.3 when pure
Hardness 2.5-3

Gold is 19.3 times heavier than an equal volume of water.

Properties of Gold Click here for more

Pure gold is soft and wears easily. It is often mixed with other harder metals. A mixture of metals is called an alloy.

Gold is very unreactive. This means it is resistant to corrosion and tarnishing. That is why a gold nugget can be buried in the ground for thousands of years and still come up looking shiny.

Gold is malleable (easily shaped) and ductile (can be drawn into very thin wire). A square lump of gold about the size of your thumb nail would weigh an ounce. That ounce of gold can be flattened into a sheet so thin that it would be thinner than a piece of refill paper and light could pass through it. It would cover an area about the size of a small bedroom. The same lump of gold can be drawn into a piece of wire 80 km long.

Uses of Gold Click here for more

Gold Reflective Glass

Gold reflects heat. This property, combined with the fact it is so malleable, means gold is often used to coat glass with a thin film which lets through light but not heat. One ounce of gold is enough to cover 93 square metres (approximately 1,000 square feet) of glass. Gold-covered glass reflects heat off the outside of a building in summer and helps to retain internal warmth in winter by reflecting the heat inside back into the room. The use of reflective glass has reduced cooling and heating costs by as much as 40% in some buildings.
 

Electronics

Gold is a very good conductor of electricity.

As we already know it is able to be drawn out into very thin wires and it doesn’t corrode or tarnish at high or low temperatures.

This means you’ve got a great material for use in complex and small electronic applications.

Gold plating on contacts for switches, relays and connectors accounts for most of the 120 to 140 tonnes of gold required each year by the electronics industry. It is used in circuits in calculators, television sets, computers, telephones and lots of other products.
 

Satellites and Communications

Gold is used in satellites as part of their electronic circuits and as a heat shield. We have come to rely on satellites for many things. They provide information about weather patterns around the world and help track the paths of storms. Satellites take photos of agricultural changes, such as diseases affecting crops, to predict production each year and help countries plan what they grow for food or trade. Satellites carry 50% of New Zealand’s international phone calls. Television companies transmit news, sports and entertainment programmes direct to viewers via satellite. Ships and aircraft use satellite tracking to determine their position. Fishermen, trampers and surveyors use global positioning systems (GPS) to accurately establish their location.
 

Aerospace

The space programme depends on the clean, non-corroding electrical performance of gold. Because the metal reflects heat it is used to protect astronauts, satellites and critical electronic components from damage by hazardous x-rays and solar radiation found in space.
 

Medicine

Compounds of gold were first used experimentally in 1927 in the treatment of rheumatoid arthritis and are still used today. Radioactive gold is used to treat several types of cancer. Gold leaf is used to treat chronic ulcers and is used in surgery to patch damaged blood vessels, nerves, bones and membranes.
 

Dentistry

Each year dentists in the United States alone use about 30 tonnes of gold. Gold alloys are used for crowns, bridges, gold inlays and dentures because of their high resistance to corrosion and tarnish.