Copper is an essential element in today’s society because it is an excellent electrical conductor. This activity explores where copper is found and how mining geologists set about finding new copper deposits.

What is copper?

Copper is a transition metal element with an atomic number of 29 (it has 29 electrons) and average atomic mass of 63.5. It has a single electron in its outermost shell that is easily transferred to other copper atoms in a crystal lattice and this property makes it a good conductor of electricity (electricity is just the movement of charged particles such as electrons). Copper is also very malleable (its bendy and doesn’t break easily) and is therefore the preferred metal to make wires and cables for transporting an electric current. It is also an essential component of printed circuit boards and integrated circuits (also known as silicon or micro-chips), because a thin layer of copper can be easily etched to leave behind a conducting circuit. Copper will play a very important role in our transition to a post carbon future because each wind turbine uses copper in the electrical generator, each solar panel will be connected to the National Grid by a copper cable and each electric vehicle needs copper for the electric motor.

Where does copper come from?

The average abundance of copper in the Earth’s crust is only 0.006% (about 60 parts per million). If this was the only source of copper we would have to process a huge volume of rock to extract the metal. Fortunately, certain geological processes concentrate copper into ore minerals. Geologists now have a good understanding of how and why these copper deposits form, and which parts of the world to search for them. We call these concentrated mineral ores Copper Porphyry Deposits. Nevertheless, these deposits are rarely exposed at the surface and exploration geologists have to use a number of different techniques to discover their precise location. Now watch the introductory video on copper exploration.

Activity

Mining engineers have to think like a detective, piecing together different geological clues to determine the best place to find new copper porphyry deposits. Have a go at being a mining engineer with this fun game.

Porphyry Exploration Game

Copper exploration A3 data sheets

Take a look at the copper exploration data sheets including explanatory diagrams and maps of an area of the world where many porphyry deposits have been found before. Rich investors have given your company money so that you can buy the exploration rights to an area. The end game is to find a viable porphyry deposit to sell to a major mining company.

You have 5 areas (A – E) which the government of this country has made available to you for exploration.

Examine all the clues on the information provided and decide which location would be the best place for a new copper mine. Think carefully about the legal, environmental, logistical, and engineering issues associated with mining.

Some Technical Notes

• All porphyry deposits previously discovered in this district are Jurassic in age, and are hosted in Precambrian rocks.

• Mineralisation has previously been found ‘under cover’; i.e. in rocks which have been covered by more recent sediments, including the Holocene-age river deposits of the area.

• Other deposits in the area have shown strong, well-developed alteration zoning

To find out which of the locations (A – E) is the ‘best’ area for exploration, view the interactive image below or visit this link.

We gratefully acknowledge the help and support of the Natural History Museum (London) and the Geological Society of London for providing the resources for this activity

Going Further: If you enjoyed learning about copper and mineral exploration you may be interested in watching these videos on copper, its origin and uses. It’s available as a single video (19 mins) or as a series of shorter chapters

Dr Ken amor

Dr Ken Amor was awarded a BSc Geology from Reading University, a MSc in Geochemistry from the University of Leeds and a D.Phil at St. Peter’s College, Oxford University. His focus is providing content for STEM projects in the Inspire program at St John’s College and supporting the College’s Outreach activities. Previous experience includes delivering sessions to teachers and prospective students, and running activities for the UNIQ Summer school and other outreach events on behalf of the central University’s Undergraduate Admissions and Outreach office, Colleges, and science departments.