"In 2016, Intel's Entire Supply Chain Will Be Conflict-Free", 5 Jan. 2016

Seven years ago, if you bought a new [smartphone] or a laptop, you were probably also inadvertently supporting warlords and mass rapists in the Democratic Republic of Congo... This year, Intel expects its entire supply chain to be conflict-free. It's taken time: the company first set the goal in 2009, and with a massive list of suppliers, it was an overwhelming challenge at first... 

Now, nonprofits work with the government to audit mines, and when a mine gets a "green" or good rating, the material that's shipped out ends up in labeled bags that can be tracked to smelting plants around the world. While it isn't a foolproof process, after auditing the mines themselves, Intel believes it works... 

There are still challenges. Gold, for example,..[is] easier to smuggle... For now, that means Intel has to buy gold from other parts of the world...