Why are rare earth elements so important?
Could rare earth elements be the next thing to affect future international relations and politics?
They are increasingly becoming more important in developing the latest high-tech products such as Ipods and tablet computers. They are vital for the red colour in your TV screen and are what allows your headphones to be small enough to fit into your ears.
The BBC's Alastair Leithead is at America's only rare earth mine and spoke to Jim Sims from Molycorp, the company that runs California's Mountain Pass mine.