Life as an unregistered gold miner
26 December 2013 Last updated at 03:01 GMT
In the remarkable gold rush that gripped Brazil's Tapajos river basin after gold was discovered in 1958, tens of thousands of individual miners, known as garimpeiros, moved into the area.
While only a few got rich, most made a much better living than they would have done in rubber-tapping, fishing or subsistence agriculture.
Although the pickings have become sparser in recent years, many men are still at work in the primitive, unregistered gold mines known as garimpos.
Video: Nayana Fernandez