Congo mines hit by conflict crackdown
15 May 2012 Last updated at 07:19 BST
Mineral mines in central Africa and the people who rely on them for a living are being hit by international reluctance to trade in conflict minerals.
Electronic companies, which can trace the origins of most of their materials, admit they cannot guarantee that the tin and precious metals used in their products do not come from illicitly-run mines.
But even at mines graded as free from exploitation and are not controlled by military or rebel armed groups, prices have suffered and companies have pulled out rather than risk contact with conflict minerals.
Humphrey Hawksley reports from eastern DR Congo.