It's Elemental

Mercury was known to the ancient Chinese and Hindus and has been found in 3500 year old Egyptian tombs. Mercury is not usually found free in nature and is primarily obtained from the mineral cinnabar (HgS). Spain and Italy produce about half of the world's supply of Mercury.

Mercury can be used to make thermometers, barometers and other scientific instruments. Mercury conducts electricity and is used to make silent, position dependent switches. Mercury vapor is used in streetlights, fluorescent lamps and advertising signs.

Mercury easily forms alloys with other metals, such as gold, silver, zinc and cadmium. These alloys are called amalgams. Amalgams are used to help extract gold from its ores, create dental fillings (in the case of silver) and help extend the life of dry cell batteries (in the case of zinc and cadmium).

Mercury forms useful compounds with other elements. Mercuric chloride (HgCl₂) is a very poisonous salt and was once used to disinfect wounds. Mercurous chloride (Hg₂Cl₂), also called calomel, is an antiseptic used to kill bacteria. Mercuric sulfide (HgS) is used to make a red paint pigment called vermilion. Mercuric oxide (HgO) is used to make mercury batteries.

Mercury is poisonous and can enter the body through the respiratory tract, the digestive tract or directly through the skin. It accumulates in the body, eventually causing severe illness or death.