 Livermorium is a synthetic superheavy element with symbol Lv and atomic number 116 . It is an extremely radioactive element that has only been created in the laboratory and has not been observed in nature . The element is named after the Lawrence Livermore National Laboratory in the United States , which collaborated with the Joint Institute for Nuclear Research in Dubna , Russia to discover livermorium in 2000 . The name of the laboratory honors the city of Livermore , California where it is located , which in turn was named after the rancher and landowner Robert Livermore . The name was adopted by IUPAC on May 30 , 2012 . Four isotopes of livermorium are known , with mass numbers between 290 and 293 inclusive ; the longest @-@ lived among them is livermorium @-@ 293 with a half @-@ life of about 60 milliseconds . 
