Mercury silvering methods. The technique was also used in Asia, for example "tokin" plating in Edo-period Japan. 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
Phenyl(trichloromethyl)mercury Phenyl(trichloromethyl)mercury Phenyl(trichloromethyl)mercury is an organomercury compound with the formula CHHgCCl. It is a white solid that is soluble in organic solvents. The compound is used as a source of dichlorocarbene, e.g. in cyclopropanation reactions, illustrated with tetrachloroethylene as a substrate, the product being hexachlorocyclopropane: The compound is prepared by treating phenylmercuric chloride with sources of dichlorocarbene. These include the base/haloform reaction and thermolysis of sodium trichloroacetate: Closely related compounds include phenyl(bromodichloromethyl)mercury (CAS registry number 3294-58-4) and phenyl(tribromomethyl)mercury (CAS registry number 3294-60-8). According to X-ray crystallography, the former has nearly linear coordination geometry at mercury, with a C-Hg-C angle of 179°