The heaviest metal on the periodic table of elements is osmium. Its density is 22.57 grams per cubic centimeter, which is twice that of the element lead. A quarter-gallon of osmium weighs 50 pounds when compared to a quarter-gallon of water, which weighs only 2.2 pounds.
Osmium is so dense that a 2-cubic-foot block of the metal weighs as much as an automobile that weighs 3,400 pounds. Metallic osmium is very difficult to make, and it is hard, brittle and mainly used to manufacture tough alloys. As of 2014, osmium is retrieved during the processing of nickel and platinum ores.