Mercury is a naturally occurring element that is found in air, water, and soil. It exists in several forms: elemental or metallic mercury, inorganic mercury compounds and organic mercury compounds.

The mercury concentration should be given on an elemental basis, not on a mercury compound basis. The default value is a function of the coal rank. •Mercury in Auxiliary Gas (elemental): This input ...

Mercury compounds were used until quite recently to make insecticides (chemicals that kill the insects that damage crops) and special paints that stop barnacles growing on the hulls of ships.