Iron Rock File

Rock Files | Fact Sheets | Minerals Downunder

General
Properties
Uses
Source
Operating Iron Mines
Amazing Facts
Further Information
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General

Iron is the backbone of the world we've built around us, as it is the basic ingredient for steel. Steel is a very strong form of iron - hence terms like 'Man of Steel' (Superman) or Iron Man competitions - and a very useful metal because it can be mixed with other metals to make a whole variety of 'alloys' which are long-lasting and able to be easily shaped into products from cars to pins, household appliances to buildings, bridges to railways, food cans to tools. In short, we rely on iron (as steel) to make almost everything we need for living in the 21st century!

Properties

Iron is unusual in being magnetic - if you dangle a piece it will turn to face north-south
Iron is a silver-grey metal which quickly corrodes or rusts (it forms a red powder called iron oxide) when exposed to air and water.
Iron is quite soft and easily worked.
When made into steel iron is very strong.
Iron has the symbol Fe from the Roman word ferrum.
Iron has a very high melting point of 1535oC.

Uses

Use	Description
Transportation	Steel railway carriages/engines, ships, car frames, engine cylinders.
Construction	Steel buildings, bridges (such as the Sydney Harbour Bridge), roofing, cladding, doors, fencing.
Machinery	Steel engines, pumps, cranes, workshop equipment (eg. cutting tools, drill bits).
Wire products	Steel wire fences, ships' cables, staples, door screens, nuts & bolts.
Storage	Steel food containers, storage tanks.
Oil and Gas	Steel drill rods, casing, pipelines.
Appliances and Equipment	Steel refrigerators, washing machines, dishwashers, cutlery, hospital equipment.
Health	Pure iron is needed for proper plant growth. Animals need iron for making energy and carrying blood around the body (foods rich in iron include red meat and liver, egg yolks and leafy green vegetables.) Iron was the first element to be recognised as essential for people. A physician in 1681 successfully used iron to treat patients who were pale, lacking in energy and suffering from anaemia. Iron chloride is used in water treatment and purification.
Fun	Iron filings are used in 'sparklers'.
Electronics	Iron chloride is used to etch copper in the making of electrical printed circuits.
Cooking	Cast iron camp ovens and woks.
Decoration	Wrought iron outdoor furniture, porch railings and other decorative items.

Source

Iron isn't usually found on its own - it is often combined with other elements in rocks. For example, haematite (from the Greek word meaning 'blood-stone') is a red ore of iron and is responsible for the red colour in our rocks and the deep red sands of the Australian deserts. Some of these rocks are more than 600 million years old! Australia has huge reserves of iron ore (mostly in the Pilbara region of Western Australia) and we supply 1/8th of the world's iron ore needs.

To make steel, the iron-ore bearing rock is first blasted and dug up from open pit mines, then crushed, smelted (heated with other substances including carbon) in huge furnaces, then combined (alloyed) with metals like nickel, chromium, manganese or titanium. These alloys give steel special properties like electrical resistance, and resistant to wear, rust, impact, shock or expansion when heated.

The cooled steel is shaped and can be coated with tin, zinc or paint to help protect it from rusting, creating products such as Zincalume and Colorbond.

Amazing Facts

The earth's magnetic field is due to the iron (and nickel) in its core, so when we use a compass we are making use of the iron underneath us.
Iron is amongst the oldest metals known to humans. Paleolithic Man used finely ground haematite as rouge! Around 4000 BC, the Egyptians and Sumerians first used iron from meteorites to make beads, ornaments, weapons and tools.
The Iron Age was from 1300 - 1100 BC, when the Hittites were the first to forge iron (they heated it, then hammered it, then cooled it quickly to produce iron that was harder than bronze, which people had been using before).
By the time of the Roman Empire, iron was being used for beds, gates, chariots, nails, saws, axes, spears, fishhooks and tools for sharpening.
During the Middle Ages, with the introduction of the iron cannon and cannon ball, the consumption of iron increased to overtake copper and bronze as the most widely used metal.
Iron was the first metal to be discovered in Australia, by explorer Edward John Eyre in the Middleback Ranges in South Australia.
In the late 19th century the Age of Steel began, with wooden ships giving way to steel, machinery coming to the factories, and the invention of the railroad.
Today we use 20 times more iron (in the form of steel) than all other metals put together.
Steel is one of the world's most recycled products, with about 60% of steel available for recycling going back into making new steel.
The value of Australia's iron ore exports is exceeded only by that of coal.