Silver the periodic table) is useful in nuclear reactors because of its high thermal neutron capture cross-section, good conduction of heat, mechanical stability, and resistance to corrosion in hot water. The word "silver" appears in Anglo-Saxon in various spellings, such as "seolfor" and "siolfor". A similar form is seen throughout the Germanic languages (compare Old High German "silabar" and "silbir"). The chemical symbol Ag is from the Latin word for "silver", "argentum" (compare Ancient Greek ἄργυρος, "árgyros"), from the Proto-Indo-European root *"h₂erǵ-" (formerly reconstructed as "*arǵ-"), meaning "white" or "shining": this was the usual Proto-Indo-European word for the metal, whose reflexes
Chemical element remaining naturally occurring chemical elements were identified and characterized by 1900, including: Elements isolated or produced since 1900 include: The first transuranium element (element with atomic number greater than 92) discovered was neptunium in 1940. Since 1999 claims for the discovery of new elements have been considered by the IUPAC/IUPAP Joint Working Party. As of January 2016, all 118 elements have been confirmed as discovered by IUPAC. The discovery of element 112 was acknowledged in 2009, and the name "copernicium" and the atomic symbol "Cn" were suggested for it. The name and symbol were officially endorsed by IUPAC on 19