Forms of Mercury in Soil, Water and Environment

Mercury belongs to group 12 of the periodic table. It is a heavy metal. It is considered as an element as well as a metal. Its periodic neighbors are Gold and Ti. Mercury has an atomic number of 80and its atomic mass is. 201. It has two main oxidation states that are +1 and +). It has seven stable isotopes (196Hg, 198Hg, 199Hg, 200Hg, 201Hg, 202Hg and 204Hg). The most abundant isotopes are 202Hg, 200Hg and 199Hg that comprises of 29. 6% 23. 3% and 17. 0% of total mass respectively.

As a heavy metal, mercury has unique properties. It is liquid at ambient temperature and is approximately 14 times heavier than water. The major mercury ore is cinnabar (mercuric sulfide or HgS), which has been mined at relatively few places on earth. The mines of Idrija (now in Slovenia) operated for more than 500 years until closed in 1995. The mercury mines at Almaden, Spain, have operated since 415 B. C. Mercury is an extremely uncommon chalcophile component, in spite of being known from times long past, on account of its intermittent appearance as the particular local metal, and its relative simplicity of arrangement from its principle mineral. Volcanic hot springs and sedimentary rocks changed by phreatic action are the fundamental wellsprings of Hg mineralization. The main mineral is cinnabar HgS, alongside the metacinnabar gathering of minerals in which variable measures of Zn and Fe substitute for Hg, and Se substitutes for S.

Other essential Hg minerals, incorporate local mercury, corderoite Hg3S2Cl 2 and livingstonite HgSb 4S 8. Auxiliary Hg minerals, incorporate schuetteite Hg3(SO4) O2 and calomel Hg2Cl2. Mercury happens likewise as a follow constituent in a few sulfides, for example, tetrahedrite Cu3SbS3. 25 and sphalerite ZnS. The expansive size of the ostensible Hg 2+ particle, together with its low level of ionic character, blocks its consolidation into many shake framing silicate minerals. Molten rocks, basalt and gabbro have by and large much lower Hg substance (normally 10 μg kg-1) than stone (normal 80 μg kg-1). Substantially higher Hg levels (up to 1500 μg kg-1) have been found in eclogite and peridotite in incorporations in kimberlite channels, proposing that the profound hull and upper mantle might be extensively advanced in Hg contrasted with the upper crustal rocks. In sedimentary rocks, normal Hg levels are higher in shale (400 μg kg-1) than in carbonate rocks (40 μg kg-1) and sandstone (30 μg kg-1).

The relative improvement of Hg in shale is significantly more set apart in some natural rich dark shale, which may hold a few mg kg-1 Hg bound to dirt minerals, natural buildups and sulfides.