Approximately 13 million metric tons of rare earth elements REE exist within known deposits in the United States, according to the first-ever nationwide estimate of these elements by the U.S. Geological Survey. At recent domestic consumption rates of about 10,000 metric tons annually, the US deposits have the potential to meet our needs for years to come REE are a group of 16 metallic elements with similar properties and structures. Despite their name, they are relatively common within the earth’s crust, but because of their geochemical properties, they are not often found in economically exploitable concentrations. Hard-rock deposits yield the most economically exploitable concentrations of REE. [See USGS]
A recent report by the American Association for the Advancement of Science concluded that a shortage of rare earth elements could significantly impact the large-scale deployment of new energy technologies and limit expansion of computing and telecommunications technologies. The report advises against strategic stockpiling by the federal government. In the past, stockpiling has stifled the incentive to develop substitute materials. Also, as the United States lacks most of these elements in significant quantities, the country cannot mine its way out of this problem. Cellphones and iPods end up in landfills despite containing more of these elements, pound for pound, than the ore they are extracted from. Still, a recycling program won't be enough, the report notes, as much of the materials will be locked up in electric car batteries and wind turbine blades for decades.
Senator Mark Udall (D-Colo.) introduced a bill directing the U.S. Geological Survey to conduct a study of the issue, a broad inquiry that would, among other things, track the global supply chain of these elements, which are often produced as byproducts of mining more abundant minerals, such as copper. The bill also calls on the Department of Energy to help secure a steady supply of the elements. Cellphones and iPods contain as many as 65 elements, many of them rare. Electric car batteries also rely on rare elements, as do blades for wind- and gas-powered turbines. The insides of energy-efficient compact fluorescent light bulbs are coated with tiny amounts of two such elements, terbium and europium.
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China has 30 percent of the world's rare-earth deposits, but the United States, Australia and others stopped mining their own a decade ago because it was cheaper to buy Chinese ores. There are concerns about the the supply of REEs because China produces about 95 percent of them. (Wash Post, 2/19/2011, Wash Post, 2/14/2011, USGS)
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