text: Minerals have been extracted from seawater since ancient times. Currently the four most concentrated metals – Na, Mg, Ca and K – are commercially extracted from seawater. During 2015 in the US 63% of magnesium production came from seawater and brines. Bromine is also produced from seawater in China and Japan. Lithium  extraction from seawater was tried in the 1970s, but the tests were soon abandoned. The idea of extracting uranium  from seawater has been considered at least from the 1960s, but only a few grams of uranium were extracted in Japan in the late 1990s. The main issue is not one of technological feasibility but that current prices on the uranium market for uranium from other sources are about three to five times lower than the lowest price achieved by seawater extraction. Similar issues hamper the use of reprocessed uranium and are often brought forth against nuclear reprocessing and the manufacturing of MOX fuel as economically unviable.