Mercury silvering Mercury silvering Mercury silvering or fire gilding is a silvering technique for applying a thin layer of precious metal such as silver or gold (mercury gilding) to a base metal object. The process was invented during the Middle Ages and is documented in Vannoccio Biringuccio's 1540 book "De la pirotechnia". An amalgam of mercury and the precious metal is prepared and applied to the object which is then heated, sometimes in oil, vaporizing most of the mercury. The technique is dangerous since mercury is highly toxic, especially in its vapor phase. Mercury silvering can be detected through a variety of
Mercury pollution in the ocean water surface. These are either driven by sunlight or by microbial activity. Under UV radiation, elemental mercury oxidizes and dissolves directly in ocean water or binds to other particles. The reverse reaction reduces some mercury Hg2+ to elemental mercury Hg(0) and returns to the atmosphere. Fine aerosols in the atmosphere such as ocean water droplets can act as small reaction chambers in this process providing the special reaction conditions required. Oxidation and reduction of mercury in the ocean are not very simple reversible reactions. Shown below is the proposed pathway of ocean aerosol mercuric photochemistry suggesting that it occurs through