![]() The human-generated half can be divided into the following estimated percentages: Natural sources such as volcanoes are responsible for approximately half of atmospheric mercury emissions. Volcanic eruptions can increase the atmospheric source by 4–6 times. ![]() Although that can be considered a natural level of exposure, regional or global sources have significant effects. Preindustrial deposition rates of mercury from the atmosphere may be in the range of 4 ng/L in the western USA. Releases in the environment File:Mercury fremont ice core.pngĪmount of atmospheric mercury deposited at Wyoming's Upper Fremont Glacier over the last 270 years See also Category:Mercury minerals, Category:Mercury mines. For example, in 1976 Santa Clara County, California purchased the historic Almaden Quicksilver Mine and proceeded to create a county park on the site, after conducting extensive safety and environmental analysis of the property. Several other countries are believed to have unrecorded production of mercury from copper electrowinning processes and by recovery from effluents.ĭue to minimal surface disruption, mercury mines lend themselves to constructive re-use. In 2005, China was the top producer of mercury with almost two-thirds global share followed by Kyrgyzstan, reports the British Geological Survey. The metal is extracted by heating cinnabar in a current of air and condensing the vapor. Many former ores in Italy, the United States and Mexico which once produced a large proportion of the world's supply have now been completely mined out or in the case of Slovenia and Spain shut down due to the fall of the price of mercury in the international markets. Over 100,000 tons of mercury were mined from the region of Huancavelica, Peru, over the course of three centuries following the discovery of deposits there in 1563 mercury from Huancavelica was crucial in the production of silver in colonial Spanish America. Mercury ores usually occur in very young orogenic belts where rock of high density are forced to the crust of the Earth, often in hot springs or other volcanic regions. It is found either as a native metal (rare) or in cinnabar, corderoite, livingstonite and other minerals, with cinnabar (Hg S) being the most common ore. The richest mercury ores contain up to 2.5% mercury by mass, and even the leanest concentrated deposits are at least 0.1% mercury (12,000 times average crustal abundance). However, because it does not blend geochemically with those elements that constitute the majority of the crustal mass, mercury ores can be extraordinarily concentrated considering the element's abundance in ordinary rock. Mercury is an extremely rare element in the earth's crust, having an average crustal abundance by mass of only 0.08 parts per million. Mercury occurs in deposits throughout the world and it is harmless in an insoluble form, such as mercuric sulfide, but it is poisonous in soluble forms such as mercuric chloride or methylmercury. Mercury is mostly obtained by reduction from the mineral cinnabar. ![]() It remains in use in a number of other ways in scientific and scientific research applications, and in dental amalgam. Mercury is used in thermometers, barometers, manometers, sphygmomanometers, float valves, and other scientific apparatus, though concerns about the element's toxicity have led to mercury thermometers and sphygmomanometers being largely phased out in clinical environments in favour of alcohol-filled, digital, or thermistor-based instruments. A heavy, silvery d-block metal, mercury is one of six elements that are liquid at or near room temperature and pressure. , meaning watery or liquid silver) and atomic number 80. Mercury ( IPA: /ˈmɜrkjʊri/), also called quicksilver is a chemical element with the symbol Hg (Latinized Greek: hydrargyrum Please help to improve this page yourself if you can. This article needs rewriting to enhance its relevance to psychologists.
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