If you speak German, you have to read this article from Spiegel. If you don't, you have to at least get the gist of it by using some machine translation tool.
I'm busy, so I can't explain the whole thing right now. It's about illegal miners, the Chinese and CITIC, interests for gold and diamonds on one side and the native Americans and the environment on the other.
I will later come back and give some details.