Indonesia gold mine 'stripped' tropical rain forest
17 September 2013 Last updated at 17:49 BST
About 15% of the world's gold is produced by artisanal and small-scale miners, many of whom use mercury to extract it from the earth.
In Indonesia, some three million people make their living from the precious metal and the income provides a financial lifeline to some communities.
However, parts of the tropical rain forest in Central Kalimantan have had to be cut back to make way for the mines.
As this video shows what gets left behind are lunar-like landscapes with pools of water polluted with mercury.