People employ various methods to extract gold in the rainforests of the Chocó, in northwest Colombia: Rural Afro-Colombian artisanal miners work hillsides with hand tools or dredge mud from river bottoms. Migrant miners level the landscape with excavators, then trap gold with mercury. Canadian mining companies prospect for open-pit mega-mines. Drug traffickers launder cocaine profits by smuggling gold into Colombia and claiming it came from fictitious small-scale mines.Through an...