On the inside of many devices like mobile phones and laptops, the mineral, 'Coltan', has made our gadgets smaller and more complex. In the mineral-rich Congo, armed militia watch over the children digging it from the ground. "The government only pretends to help us" says one miner, who pays a government official just to work. "The Congo is a shifting sands of various militia, the largest of which is the Congolese state itself" explains an expert on blood minerals. Yet the miners depend on the little they get from mining to survive. Electronic giants like Apple now claim they will no longer use Coltan from this area but experts are convinced the militias will "smuggle it onto the market" regardless. For local miners, the move away from African minerals is "just another way of penalising Africans". Coltan fuels a conflict, which has seen national parks become war zones, gorillas killed for meat and hundreds of houses set on fire in turf wars over mineral territory. Yet it also feeds 400,000 petty traders. Why did it take a mobile phone to make us appreciate the injustice in the Congo?