Welcome to the elements
The periodic table provides an entirely new perspective on how the global economy works, as we discover in the first part of a new series about the chemical elements.
A mining engineer working with Rio Tinto explains the geological processes that took millions of years to create the useful concentrations of these fundamental building blocks, and the often brutal process of extracting them.
We hear about a project to dissect mobile phones in order to highlight the disturbing stories behind some of the 40 elements they contain.
And we take a guided tour of the London Metals Exchange - the world's main trading forum for 11 of the biggest elements.
21 Feb 2014