Around 70 per cent of the world's cobalt is mined in the Democratic Republic of Congo, mostly from the southern Katanga area. Reporter Jamal Osman travels to Kolwezi, a city dependent on supplying cobalt, a critical component for electric cars and rechargeable batteries. Residents are employed by large multinational companies, or in smaller and more dangerous artisanal mines where men clamber down dark weaving airless tunnels. Osman contemplates whether the rewards are worth the health risks that doctors have highlighted with the by-products and pollution from mining.