Conflicts, including the Rwandan occupation in the east of the Democratic Republic of Congo (DRC) made it difficult for the DRC to exploit its coltan reserves. Mining of the mineral is mainly artisanal and small-scale. A 2003 UN Security Council report^[ charged that a great deal of the ore is mined illegally and smuggled over the country's eastern borders by militias from neighbouring Uganda, Burundi and Rwanda.

All three countries named by the United Nations as smugglers of coltan have denied being involved. Austrian journalist Klaus Werner has documented links between multi-national companies like Bayer and the illegal coltan traffic. A United Nations committee investigating the plunder of gems and minerals in the Congo listed in its final report^[18] approximately 125 companies and individuals involved in business activities breaching international norms. Companies accused of irresponsible corporate behavior are for example the Cabot Corporation, Eagle Wings Resources International Forrest Group and OM Group.

Coltan smuggling likely provides income for the military occupation of Congoas well as prolonged civil conflict. To many this raises ethical questions akin to those of blood diamonds. Owing to the difficulty of distinguishing legitimate from illegitimate mining operations, several processors such as Cabot Corp (USA) have decided to forgo central African coltan altogether, relying on other sources.

Much coltan from the DRC is being exported to China for processing into electronic-grade tantalum powder and wires.

Estimates of the Congo's fraction of the world's coltan reserves range from 64% and up. Tantalum, the primary mineral extracted from Coltan is also mined from other sources, and Congolese coltan represented around 10% of world production in recent years.