Iron is an essential element in plants, and helps our blood transport oxygen around our bodies

Today, steel is an essential part of our modern world, and drives demand for the iron ore produced by Rio Tinto in Australia and Canada.

But iron played a fundamental role in life long before steel was invented – it’s an essential element in plants, and helps our blood transport oxygen around our bodies.

Here are ten facts about the world’s most used metal:

1. Iron is a silvery-white metallic element. Its chemical symbol is Fe – which comes from the Latin word for iron, “ferrem”.

2. One third of Earth’s mass is believed to be iron, most of which lies deep within the Earth’s core. Scientists believe it’s the flow of liquid iron deep within the Earth that creates the electric currents that generate our planet’s magnetic field.

3. Iron is also abundant in the Earth’s crust – it’s the fourth most common element after oxygen, silicon and aluminium. Iron is not found on its own in nature, but in minerals such as hematite and magnetite.

4. Iron is found in the sun, other stars and planets, and meteorites. The Hoba meteorite in Namibia contains more than 80 per cent iron and is the largest naturally occurring piece of iron on the Earth’s surface.

How iron has shaped our world How iron has shaped our world
Iron ore is the key ingredient in the production of steel

20x

more iron is used than all other metals put together

5. Iron has been used for about 5000 years. But as iron ore smelting techniques weren’t widely adopted until around 1200BC, it is thought that the first iron used by humans was likely to have come from meteorites. The onset of the Iron Age saw the widespread use of iron in tools and weapons, and led to a period of great social change. Iron tools made farming more efficient, and allowed people to try new crops and farm tougher soils.

6. Today, iron is still the most useful metal known. It is the key ingredient in the production of steel – an essential part of modern living from buildings to transportation, machinery to household appliances. According to Geoscience Australia, the world uses 20 times more iron (in the form of steel) than all other metals put together.

7. Steel is strong, durable and relatively low cost, making it well suited for use as a structural metal in engineering and building projects. About 60 per cent of all iron and steel products are used in transportation and construction.

8. In its pure form, iron is quite soft. It’s combined with other metals to create alloys that make it stronger and suited to different uses. The most common iron alloy is iron and carbon – otherwise known as steel. Another common alloy is iron, carbon, chromium and nickel which together create rust-resistant stainless steel.

9. Ever wondered why your blood is red? The haemoglobin molecules in our blood contain iron to help transport oxygen from our lungs to the tissues in our body. The reaction between iron and oxygen creates a red hue. It’s the same chemical reaction that causes rust.

10. Nature could hold the key to new and improved uses for iron. According to the Ecological Society of America, in 1999 scientists discovered a deep-sea snail that uses an iron-plated shell as protection from predators. The snail, which was found living in iron-rich hydrothermal vents in the Indian Ocean, absorbs iron sulphide from the water to strengthen its shell. It’s unlike any other natural or synthetically engineered armour, and is being studied to give insights into building stronger materials.

Find out more about Rio Tinto’s Iron Ore business.