and again...what is "red mercury" ? "A 15–40% (usually about 30%) solution of tributyl phosphate in kerosene or dodecane is used in the liquid–liquid extraction (solvent extraction) of uranium, plutonium, and thorium from spent uranium nuclear fuel rods dissolved in nitric acid, as part of a nuclear reprocessing process known as PUREX. The shipment of 20 tons of tributyl phosphate to North Korea from China in 2002, coinciding with the resumption of activity at Yongbyon Nuclear Scientific Research Center, was seen by the United States and the International Atomic Energy Agency as cause for concern; that amount was considered sufficient to extract enough material for perhaps three to five potential nuclear weapon"