2011_PNG_mercuryextraction

Illegal miners begin the gold extraction process by crushing rocks into dust in Porgera, Papua New Guinea. They then wash as many undesirable rock particles out of the dust as possible, and pour mercury into the remaining material. The mercury binds to any gold present in that material, creating a gold-mercury amalgam that excludes everything else. This amalgam is cooked over an open flame, causing the mercury to turn into vapor and escape into the air. The miners are left with pure gold, which they can sell on the open market.

© 2011 Brent Stirton/Getty images for Human Rights Watch