An introduction to geology
An introduction to geology

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

Free course

An introduction to geology

2.21 Ancient people and metals

Finding the correct rocks to dig out of the ground does not happen by accident. In this section you will look at how ancient and modern humans have found the metals they need.

Have you ever wondered how geologists find minerals and work out where mines should go? And how did ancient people like those of the Bronze Age find metals?

Copper was the first metal to be worked by humans. In northern Iraq, 8000-year-old copper beads have been found. Then, 6000 years ago, gold was used in burial sites in Bulgaria, and apart from a lead bracelet that is 5500 years old, the only metals humans used for over 4000 years were gold and copper. But why?

The simple answer is that these metals, and a few others, occur in their ‘native forms’ – as a naturally occurring piece of metal, not combined with other elements to form a mineral. These ancient people wouldn’t have had to extract it from the rock themselves. They probably found them as nuggets in rivers, just like people do today if they go panning for gold (if they are lucky!). Later, they would have found layers of the native metals in the rocks (we call these ‘veins’) and mined those.

Described image
Figure 2.21 Native gold and copper

Once the majority of these nuggets had been exhausted, new sources of these metals had to be found. The main reason copper was used a lot was because its ore minerals (minerals that contain metals) are easy to find because of their amazing colours.

Do you know the colour most typically associated with copper (apart from the coppery orange–brown colour of the native metal)? It’s a blue–green colour. You may have seen it on buildings or statues and not actually known it was copper. The copper oxidises when exposed to the ‘wet’ atmosphere, producing a pigmentation commonly known as verdigris. The most famous example of a copper object showing this colour is probably the Statue of Liberty in the USA.

Described image
Figure 2.22 Statue of Liberty

Natural copper minerals also have blue–green colours, such as malachite and chalcopyrite, so these were easy for ancient humans to find.

Can you think of any other buildings or statues near you that are the same colour as the Statue of Liberty?

OUFL_1009

Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to University-level study, we offer two introductory routes to our qualifications. You could either choose to start with an Access module, or a module which allows you to count your previous learning towards an Open University qualification. Read our guide on Where to take your learning next for more information.

Not ready for formal University study? Then browse over 1000 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus371