That smart phone in your pocket contains a bit of coltan — a prized mineral that helps move electronic signals across ubiquitous microchips and controllers and allows devices to work well in extreme temperatures. And coltan is a strategic mineral because it’s important for controls on smart bombs, for example.

But coltan is also a conflict mineral, with large supplies coming from parts of Central Africa controlled by warring factions and criminal organizations that employ small-scale miners in terrible conditions, or charge them taxes to operate their claims.

For several months, ICIJ reporters in six countries combed government and court records and interviewed mining experts and brokers. The reporters also followed miners as they prospected for coltan in South America’s Amazon, in the border between Venezuela and Colombia, where they face cross-border smugglers and must deal with violent drug traffickers and paramilitaries — conditions similar to those in Central Africa.

Lack of regulation, transparency and security make this area a new source of conflict minerals, experts say, and one in which an array of human rights abuses is already taking place.

The Team:

Reporters: Emilia Diaz-Struck and Joseph Polizsuk (Venezuela);  Ignacio Gómez (Colombia); Marcelo Soares (Brazil); Nari Kim (South Korea)

Project manager: Ricardo Sandoval

Editors: Ricardo Sandoval and Gerard Ryle

Media Partners: El Universal (Venezuela), Arman-do.info (Venezuela), Noticias Uno (Colombia), El Espectador (Colombia)