Meet the Pork-Knockers of Guyana's Gold Rush

This work requires a team to dig down to the clay level of the soil, tearing up the thick rainforest in the process. The clay that might contain gold is then blasted apart with a high-pressure water jet. The water is then pumped through a channel with a sieve bottom and any gold, the densest material, settles in this tray while the waste runs off.
Mercury is stirred into what remains, which clings to the gold and removes it from the mixture. The quicksilver is then heated to 675 degrees Fahrenheit, evaporating the mercury and leaving the gold behind.
Most pork-knockers don't wear gloves or masks while practicing this highly toxic method, so mercury poisoning is common.
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