How metals are extracted from rocks underground

What Are Ores?

Deep underground, metals don't float around by themselves. They're trapped inside rocks called ores. An ore is a rock that contains useful metal mixed with other unwanted material called gangue (say: gang). Think of it like chocolate chips scattered through a biscuit — you want the chocolate, not the biscuit itself.

Mining the Ore

First, we have to dig up the ore from the ground. This happens in big mines, either on the surface or deep underground. Workers use explosives and huge machines to blast and scoop out the rock. Then the ore gets transported to a special factory called a smelter.

Crushing and Concentrating

At the smelter, the ore is crushed into powder so it's easier to work with. Next, workers separate the metal-rich bits from the worthless gangue using water and special chemicals. This leaves behind a concentrated ore that has much more metal in it.

Extracting the Metal

Now comes the clever bit. There are three main methods to pull the metal out:

Heating (Smelting): The concentrated ore is heated to very high temperatures — sometimes over 1,500°C! At this temperature, the metal melts and separates from the gangue. The molten metal drains away and cools into solid blocks called ingots.

Chemical Reactions: Some metals react with chemicals to separate from the ore. For example, iron ore reacts with carbon monoxide to release the iron metal.

Electricity (Electrolysis): For some metals like aluminium, we use electric current to force the metal to separate from the ore. This method is very powerful but uses lots of electricity.

Refining the Metal

The metal we get isn't pure yet — it still has tiny amounts of other elements mixed in. To make it pure enough for use, we refine it further using heat or electricity. This produces pure metal ingots ready to be used in cars, buildings, phones, and everything else we make.

The whole process takes months and uses enormous amounts of energy, which is why recycling metals is so important!

What Are Ores?

Metals hide inside rocks underground. These rocks are called ores. The metal is mixed with useless rock called gangue. We need to separate them.

Digging It Up

Big machines dig ore out of mines. Some mines are underground. Some mines are on the surface. The ore gets taken to a factory called a smelter.

Breaking It Down

Workers crush the ore into powder. They mix it with water and chemicals. This separates the metal bits from the waste. Now we have a mix that's mostly metal.

Getting the Metal Out

There are three main ways to extract metal:

1. Heating: We heat the ore to very high temperatures — hotter than 1,500°C! The metal melts like ice cream in the sun. It drains away and cools into solid blocks called ingots.

2. Chemistry: We mix the ore with chemicals. They react together. This makes the metal come free from the ore.

3. Electricity: We use electric current to pull the metal out. This works really well but uses lots of power. We use this for metals like aluminium.

Making It Pure

The metal we extract still has other stuff mixed in. We heat it again or use electricity again. This makes it pure metal. Now it's ready to use in cars, phones, and buildings!