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Monazite
Thorium is a silvery radioactive, metallic element. The primary source of the world's thorium is the rare-earth-and-thorium-phosphate mineral monazite. Monazite is not recovered as a salable product in the United States. Past production had been as a byproduct of titanium and zirconium mineral processing during which monazite was recovered for its rare-earth content. Nonenergy uses of thorium include high-temperature ceramics, catalysts, and welding electrodes. No thorium production or consumption has been reported in the United States for several years.
Source: http://resourcescommittee.house.gov/subcommittees/emr/usgsweb/photogallery/ ; English Wikipedia, original upload 3 August 2004 by Chris 73
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