Miners waiting for the ore to be extracted
Traditional Gold Mining and Processing
Gold-bearing rocks buried deep in the earth are mined using primitive tools such as pickaxes, spades and hammers. The recovered ore is sorted, dried in the sun, and once dry, fed into the crusher. The crushed ore is now a powder, several microns in size. This is added to water to make a slurry which is left to slide slowly down a sluice box using heavy sacks to capture fine gold particles.
Gold is left on the sacks, with the tailings (waste) flowing away into the ponds. The sacks are removed and washed in a big basin of water. Now this is where mercury comes into play. The infamous substance naturally binds gold along with other precious metals such as silver, acting as a glue separating out gold from worthless waste rock during the so-called washing/panning process. The concentrate captured during sluicing is mixed with mercury, and gets stirred around using bare hands – traditionally by women or children. After several minutes, a small ball of gold and mercury forms. This amalgam is then burnt over a hot flame on a spoon: the mercury vaporises, leaving behind a gold sponge. Mercury amalgamation is fast, easy and the substance is readily available, making this process very attractive to the local population.
The long-term consequences of mercury use, however, are most severe, causing disabilities, miscarriages and even death.
Awareness of the dangers of mercury use is on the rise, and the leaders of local mining organisations wanted to adopt mercury-free processing alternatives.