The element mercury is the most dense liquid and is even more dense than many solids. It has a density of 13.5336 grams per cubic centimeter. Mercury is the only pure metal element that is a liquid at room temperature.
Mercury's chemical symbol is Hg, which comes from the Greek word "hydrargyrum," meaning "liquid silver." It is not typically found in nature, but rather is found as the mineral cinnabar, or HgS. Mercury is more dense than water and lead.
Mercury has commonly been used in barometers and thermometers. However, the metal is poisonous. Mercury that accumulates in the body can cause severe illness over time and may result in death.