User blog comment:Tiredman2/Mass Effect Plot Holes and Contradictions/@comment-1900300-20120821064837/@comment-1388547-20120822071533

For Bekenstein, there's probably an even simpler explanation for why you can't mine it -- it probably still has good resource deposits, but they've all been discovered and claimed, and are probably actively policed, meaning there's no chance for the Normandy to swoop in and grab some of that lovely platinum.