In the third part of his Brazilian odyssey, Michael Palin visits the source of Brazil's great mineral wealth and then travels to one of the world's greatest cities to see how this new-found wealth is being spent, changing the lives of millions of its inhabitants. Michael starts this leg of the journey in the mineral-rich state of Minas Gerais - General Mines. He visits an old gold mine once owned by the British, before going to see a vast opencast iron ore mine that is such a feature of the Minas landscape. Iron ore deposits that are fuelling Brazil's economic miracle but there is always an environmental price to pay, and Michael meets some ordinary Brazilians who are dedicated to preserving the natural beauty of the state. After Minas it's down to Rio de Janeiro, host to the next Olympics and World Cup.

• Michael Palin