Copper and steel definitely aren’t the same, but how different are they?
One’s an element, one’s an alloy
Copper is a pure element, meaning it contains nothing but atoms of copper metal. Steel is not an element; it’s an alloy, or a metal combination of more than one element — in this case, steel is made by mixing iron and various amounts of carbon (and sometimes other elements as well). Pure iron is softer and more malleable, but the carbon atoms potentially make steel harder and stronger. By changing the amount of carbon we put in the steel, we can customize its properties.
We’ve been using copper a lot longer
Steel has been around longer than you think — maybe even 4,000 years ago, people were making iron with at least some carbon in it. The oldest large-scale steel production we know of was Wootz steel, made in India in about 600 BCE. But copper use is even older! Because it can be found in the ground in more or less pure usable form, we didn’t need to learn how to smelt and purify copper ore before we could start making stuff out of it. Small-scale copper use has been documented almost 10,000 years ago, and humans were learning to smelt, cast, and alloy with copper thousands of years before we figured out how to make steel.
How they’re made today
Most copper today is acquired in pit mines in the Americas in the form of copper sulfides, which are then purified. Copper mines are still operating today in Utah and New Mexico, but Chile produces more copper than anywhere else in the world. We also get a lot of copper from recycling old products, which is good because at the rate we’re currently mining, there won’t be enough left in about 50 years to be worth digging up. Hold on to your copper, it might be worth something! Modern steel is almost always formed from a base of pig iron, which we then add carbon to using various processes. The most efficient carbon process today is BOS, which stands for Basic Oxygen Steelmaking. The steel made this way has fewer impurities and can be produced more quickly than before. We also get a lot of steel, almost 40%, from recycling. The largest producer of modern steel is China.
What do we use them for?
Steel is one of the most important construction materials used by humans today. Our large infrastructure (roads, skyscrapers, bridges, etc.) are often made by building a steel frame to reinforce concrete or other materials. It’s also still the primary material used in cars, which outnumber humans in some parts of the world, and in many machines and construction materials like nails. Basically, if you want a strong metal, you use steel. Copper is no longer used to make spears and armor, but it’s still quite useful today — in the digital age, more than ever. Copper has turned out to be a great conductor of electricity and is commonly used in wiring and other electronic applications. It’s also often used to plate the outside of buildings and sometimes to create antimicrobial surfaces for humans to touch without spreading disease. Weathered copper turns green and gives the Statue of Liberty her classic appearance.