This is actually a big topic on wall street (or was a few months ago). China processes about 90% of the world's reserves of REMs, but only contains about 50% within their boarders (according to the USGS). Chinese officials also declared that they will restrict export of REMs to comply with the World Trade Organization's Article 20 saying that they are "conserving natural resources". Funny that conserving natural resources allows you the ability to manipulate prices as well. That being said, many people speculated that market price for REM's would skyrocket. They haven't played out so well though. But as far as that idea, unless you give a mean handjob, good luck finding an investor to spot you a couple million to do that geolocial survey.

But if you can find an investor, there's large potential in Africa and cheap labor I hear as well