It's really not that simple at all. Please read this report:
https://www.globalwitness.org/sites/default/files/pdfs/repor...Buying minerals from the wrong people in the DRC doesn't mean you buy from people who benevolently employ children to save them from starvation. It means you buy from the people that set up roadblocks and extort minerals from civilians in exchange for nothing (other than not shooting them). It means buying minerals from organisations that are gang raping women and kidnapping children. Buying from those people further funds their operations, making the situation for civilians worse.
The report makes recommendations, including a section "to companies and traders purchasing, handling or trading in minerals originating from eastern drc or neighbouring countries":
>Exercise stringent due diligence regarding their mineral supplies: find out exactly where the minerals were produced (not only the broad geographical area, but the precise location and mine), by whom they were produced and under what conditions (including use of forced labour, child labour, health and safety and other labour conditions).
>Refuse to buy minerals if the above information is not available or if there are indications that the minerals have passed through the hands of any of the warring parties, benefited them in other ways, or otherwise involved human rights abuses.
>Be able to demonstrate, with credible written evidence, the exact origin of their mineral supplies, the routes they have taken and the identity of those involved in the chain of custody, including intermediaries or third parties who have handled them.
>Do not accept oral or vague assurances from suppliers as to the origin of minerals and the identity of their own suppliers. Carry out spot checks to verify the sources and the accuracy of suppliers’ assurances. Require these measures in all circumstances, including in cases where minerals originate from areas which may be remote or difficult to access.
>Commission and publish regular independent third-party audits of their supply chain.
>Federations and associations of comptoirs and other trade bodies: adopt an explicit policy not to buy or handle minerals which benefit any of the warring parties in eastern DRC. Require their members to carry out the above due diligence steps systematically and to demonstrate precisely where all their supplies come from. Set up mechanisms for independently monitoring and checking whether their members are complying with these requirements.