Madagascar is one of the poorest countries in the world, with more than half the population living well below the World Bank's poverty line of $1 a day. The country also has one of the largest gem stone deposits on the planet. The sapphire trade directly links the very poorest to some of the world's richest people.
Along the Onihaly river, temporary communities of up to 3,000 people are thrown together in the hunt for remote sapphire deposits before moving along the river to try again.