Much of the world's supply of coltan comes from the Democratic Republic of the Congo. A recent UN Security Council report charged that a great deal of it is illegally mined and smuggled out of Congo by armies from Uganda, Rwanda, and Burundi, occupying the eastern region of Congo. One estimate has the Rwandan army making $250 million in 18 months from the sale of coltan, even though Rwanda has no coltan deposits.
Not only does this help finance these armies' war efforts in Congo, it is alleged, but it also has severe environmental repercussions on the forests and wildlife of the area.
They are alleged to sell this mineral, and others that they mine, in order to finance their occupation; to many, this raises ethical questions akin to those of blood diamonds. Owing to the difficulty of distinguishing legitimate from illegitimate mining operations, several electronics manufacturers have decided to forgo central African coltan altogether, relying on other sources in Australia.
All three countries named by the United Nations as smugglers of coltan have denied being involved.
See also: List of minerals