Thursday, April 15, 2010
Alchemists and mercury
A heavy, silvery d-block metal, mercury is one of five metallic chemical elements that are liquid at or near room temperature and pressure, says Wikipedia.
Mercury occurs in deposits throughout the world mostly as cinnabar (mercuric sulfide), which is the source of the red pigment vermilion, and is mostly obtained by reduction from cinnabar. Cinnabar is highly toxic by ingestion or inhalation of the dust.
Mercury is used in thermometers, barometers, manometers, sphygmomanometers, float valves, and other scientific apparatus.
Mercury was found in Egyptian tombs that date from 1500 BC. It was also known to the ancient Chinese. In China and Tibet, mercury use was thought to prolong life, heal fractures, and maintain generally good health. One of China's emperors, Qín Shǐ Huáng Dì — allegedly buried in a tomb that contained rivers of flowing mercury on a model of the land he ruled, representative of the rivers of China — was killed by drinking a mercury and powdered jade mixture (causing liver failure, poisoning, and brain death) intended to give him eternal life.
The ancient Greeks used mercury in ointments; the ancient Egyptians and the Romans used it in cosmetics which sometimes deformed the face. By 500 BC mercury was used to make amalgams with other metals. The Indian word for alchemy is Rasavātam which means "the way of mercury".
Alchemists thought of mercury as the First Matter from which all metals were formed. They believed that different metals could be produced by varying the quality and quantity of sulfur contained within the mercury. The purest of these was gold, and mercury was called for in attempts at the transmutation of base (or impure) metals into gold, which was the goal of many alchemists.