In this undated photo provided by the U.S. Geological Survey is a rock sample being analyzed in a Denver laboratory consisting of quartz, fine grain (microscopic) pyrite, galena and sphalerite. The ... more 
In this undated photo provided by the U.S. Geological Survey is a rock sample being analyzed in a Denver laboratory consisting of quartz, fine grain (microscopic) pyrite, galena and sphalerite. The USGS Mineral Resources program is looking at samples from previously mined ore that may contain critical minerals including rare earth elements. Across the West, early miners digging for gold, silver and copper had no idea that one day something even more valuable would be hidden in the piles of dirt and rocks they tossed aside. Now there's a rush in the U.S. to find key components of cellphones, televisions, weapons systems, wind turbines, MRI machines and the regenerative brakes in hybrid cars, a group of versatile minerals on the periodic table called rare earth elements and old mining tailings piles just might be the answer. (AP Photo/U.S. Geological Survey) less 
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Associated Press | Photo By U.S. Geological Survey
Sun, Jul 21, 2013 1:22 PM EDT