<p>MERERANI, Tanzania -- In the shadow of Mount Kilimanjaro, miners with flashlights tied to their heads crawl hundreds of feet beneath the East African plain, searching for a purple-brown crystal that will turn into a blue gem called tanzanite.</p>
<p>Many of the rare stones chipped off by the spacemen, as the miners are called, find their way to display cases at Zales, QVC or Tiffany. But it's a long way from these dusty plains to U.S. jewelry stores, and the stones pass through many hands on their journey. Some of those hands, it is increasingly clear, belong to active supporters of Osama bin Laden.</p>