Rare earth minerals are vital to modern human life - but you probably haven’t heard of them. They’re in our phones, computers and cars. These minerals aren’t actually that rare, but they’re difficult to extract - and this process can be pretty damaging to the environment. Mining just one tonne of rare earth minerals creates 2,000 tonnes of toxic waste. China has been mining rare earths since the 1950s and now the rest of the world is scrambling to find their own reserves.

The BBC’s Climate and Science reporter Esme Stallard explains what rare earths are, and why they matter. And BBC China correspondent Laura Bicker has been to visit two of the most important rare earth mining sites in the country. She tells us about the visit and the pollution their extraction has caused.

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