ETYM Latin Mercurius; akin to merx wares.
Or quicksilver; Heavy, silver-gray, metallic element, symbol Hg (from Latin hydrargyrum), atomic number 80, relative atomic mass 200.59. It is a dense, mobile liquid with a low melting point (-38.87şC/-37.96şF). Its chief source is the mineral cinnabar, HgS, but it sometimes occurs in nature as a free metal.
Its alloys with other metals are called amalgams (a silver-mercury amalgam is used in dentistry for filling cavities in teeth). Industrial uses include drugs and chemicals, mercury-vapor lamps, arc rectifiers, power-control switches, barometers, and thermometers.
Mercury is a cumulative poison that can contaminate the food chain, and cause intestinal disturbance, kidney and brain damage, and birth defects in humans. (The World Health Organization’s “safe” limit for mercury is 0.5 milligrams of mercury per kilogram of muscle tissue). The discharge into the sea by industry of organic mercury compounds such as dimethylmercury is the chief cause of mercury poisoning in the latter half of the 20th century. Between 1953 and 1975, 684 people in the Japanese fishing village of Minamata were poisoned (115 fatally) by organic mercury wastes that had been dumped into the bay and had accumulated in the bodies of fish and shellfish.
The element was known to the ancient Chinese and Hindus, and is found in Egyptian tombs of about 1500 BC. It was named by the alchemists after the fast-moving god, for its fluidity.
Mercury forms an amalgam with gold and so is used in gold mining to extract gold from low-grade deposits. Each year 250–300 metric tons are used in the Amazon basin alone. In 1990 mercury concentrations in edible fish close to the mining sites were 10 times greater than the WHO recommended limits for human consumption.
A heavy silvery toxic univalent and bivalent metallic element; the only metal that is liquid at ordinary temperatures; SYN. quicksilver, Hg, atomic number 80.