What is Mercury ?

Mercury occurs naturally in the environment and exists in a large number of forms. Like lead or cadmium, mercury is a constituent element of the earth, a heavy metal.

In pure form, it is known alternatively as "elemental" or "metallic" mercury (also expressed as Hg(0) or Hg0). Mercury is rarely found in nature as the pure, liquid metal, but rather within compounds and inorganic salts.

Mercury can be bound to other compounds as monovalent or divalent mercury (also expressed as Hg(I) and Hg(II) or Hg2+, respectively). Many inorganic and organic compounds of mercury can be formed from Hg(II).

The higher the temperature, the more vapours will be released from liquid metallic mercury. Some people who have breathed mercury vapours report a metallic taste in their mouths.

Mercury is mined as mercuric sulphide (cinnabar ore). Through history, deposits of cinnabar have been the source ores for commercial mining of metallic mercury.

The metallic form is refined from mercuric sulphide ore by heating the ore to temperatures above 540º C. This vaporises the mercury in the ore, and the vapours are then captured and cooled to form the liquid metal mercury.

Mercury was named after the Roman god "Mercurius", the messenger of Jupiter who was the god of commerce.

The Latin word "Mercurius" is thought to have derived from the Latin 'merx' meaning merchandise. The symbol Hg is from the Greek words hydor and argyros, meaning "water-silver", because it is a liquid like water and has silvery metallic sheen.

As a general overview of the element we can at first describe Mercury as a liquid. It is a liquid at room temperature and one of the 20 least common elements.

It is a poisonous, metallic element Mercury is occasionally found free in nature but usually occurs as the red sulfide ore, called cinnabar, or vermillion. The largest producer of mercury is the USA followed by Spain and Italy. The mercury mines of Spain have long been famous.

Mercury is extensively used in the construction of scientific instruments, such as the thermometer and barometer, and as a liquid over which to collect gases which are soluble in water.