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Mercury Sulfide
Mercury sulfide, or mercury(II) sulfide is a chemical compound composed of the chemical elements mercury and sulfur. It is represented by the chemical formula HgS. It is virtually insoluble in water. Crystal structure HgS is dimorphic with two crystal forms: * red cinnabar (α-HgS, trigonal, hP6, P3221) is the form in which mercury is most commonly found in nature. Cinnabar has rhombohedral crystal system. Crystals of red are optically active. This is caused by the Hg-S helices in the structure. * black metacinnabar (β-HgS) is less common in nature and adopts the zinc blende (''T''2d-''F'3m'') crystal structure. Preparation and chemistry β-HgS precipitates as a black solid when Hg(II) salts are treated with H2S. The reaction is conveniently conducted with an acetic acid solution of mercuric acetate. With gentle heating of the slurry, the black polymorph converts to the red form. β-HgS is unreactive to all but concentrated acids. Mercury is produced from the cinnab ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinnabar
Cinnabar (), or cinnabarite (), from the grc, κιννάβαρι (), is the bright scarlet to brick-red form of mercury(II) sulfide (HgS). It is the most common source ore for refining elemental mercury and is the historic source for the brilliant red or scarlet pigment termed vermilion and associated red mercury pigments. Cinnabar generally occurs as a vein-filling mineral associated with recent volcanic activity and alkaline hot springs. The mineral resembles quartz in symmetry and in its exhibiting birefringence. Cinnabar has a mean refractive index near 3.2, a hardness between 2.0 and 2.5, and a specific gravity of approximately 8.1. The color and properties derive from a structure that is a hexagonal crystalline lattice belonging to the trigonal crystal system, crystals that sometimes exhibit twinning. Cinnabar has been used for its color since antiquity in the Near East, including as a rouge-type cosmetic, in the New World since the Olmec culture, and in C ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zincblende (crystal Structure)
In crystallography, the cubic (or isometric) crystal system is a crystal system where the unit cell is in the shape of a cube. This is one of the most common and simplest shapes found in crystals and minerals. There are three main varieties of these crystals: *Primitive cubic (abbreviated ''cP'' and alternatively called simple cubic) *Body-centered cubic (abbreviated ''cI'' or bcc) *Face-centered cubic (abbreviated ''cF'' or fcc, and alternatively called ''cubic close-packed'' or ccp) Each is subdivided into other variants listed below. Although the ''unit cells'' in these crystals are conventionally taken to be cubes, the primitive unit cells often are not. Bravais lattices The three Bravais lattices in the cubic crystal system are: The primitive cubic lattice (cP) consists of one lattice point on each corner of the cube; this means each simple cubic unit cell has in total one lattice point. Each atom at a lattice point is then shared equally between eight adjacent cube ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury(I) Sulfide
Mercury(I) sulfide or mercurous sulfide is a hypothetical chemical compound of mercury and sulfur, with elemental formula . Its existence has been disputed; it may be stable below 0 °C or in suitable environments, but is unstable at room temperature, decomposing into metallic mercury and mercury(II) sulfide (mercuric sulfide, cinnabar).Ronald L. Rich (2007): "Zinc through Mercury". In: ''Inorganic Reactions in Water'', pages 289–306. Published by Springer. History This compound was described in the 19th century by Berzelius as a black precipitate obtained by passing hydrogen sulfide through solutions of mercury(I) salts.Berzelius, ''Lehrb.''Berzelius: ''Archiv des Apotheker Vereins im nördlichen Deutschland''.Charles Baskerville (1903): "Mercurous sulphide". ''Journal of the American Chemical Society'', volume 25, issue 8, pages 799–800. As of 1825, the London Pharmacopoeia listed a compound called "Ethiops-mineral" or ''Hydrargyri Sulphuretum Nigrum'' ("black s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercury Poisoning
Mercury poisoning is a type of metal poisoning due to exposure to mercury. Symptoms depend upon the type, dose, method, and duration of exposure. They may include muscle weakness, poor coordination, numbness in the hands and feet, skin rashes, anxiety, memory problems, trouble speaking, trouble hearing, or trouble seeing. High-level exposure to methylmercury is known as Minamata disease. Methylmercury exposure in children may result in acrodynia (pink disease) in which the skin becomes pink and peels. Long-term complications may include kidney problems and decreased intelligence. The effects of long-term low-dose exposure to methylmercury are unclear. Forms of mercury exposure include metal, vapor, salt, and organic compound. Most exposure is from eating fish, amalgam-based dental fillings, or exposure at a workplace. In fish, those higher up in the food chain generally have higher levels of mercury, a process known as biomagnification. Less commonly, poisoning may occur a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Castner–Kellner Process
The Castner–Kellner process is a method of electrolysis on an aqueous alkali chloride solution (usually sodium chloride solution) to produce the corresponding alkali hydroxide, invented by American Hamilton Castner and Austrian Carl Kellner in the 1890s. History The first patent for electrolyzing brine was granted in England in 1851 to Charles Watt. His process was not an economically feasible method for producing sodium hydroxide though because it could not prevent the chlorine that formed in the brine solution from reacting with its other constituents. American chemist and engineer, Hamilton Castner, solved the mixing problem with the invention of the mercury cell and was granted a U.S. patent in 1894. Austrian chemist, Carl Kellner arrived at a similar solution at about the same time. In order to avoid a legal battle they became partners in 1895, founding the Castner-Kellner Alkali Company, which built plants employing the process throughout Europe. The mercury cell process ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calcium Sulfate
Calcium sulfate (or calcium sulphate) is the inorganic compound with the formula CaSO4 and related hydrates. In the form of γ-anhydrite (the anhydrous form), it is used as a desiccant. One particular hydrate is better known as plaster of Paris, and another occurs naturally as the mineral gypsum. It has many uses in industry. All forms are white solids that are poorly soluble in water.Franz Wirsching "Calcium Sulfate" in Ullmann's Encyclopedia of Industrial Chemistry, 2012 Wiley-VCH, Weinheim. Calcium sulfate causes permanent hardness in water. Hydration states and crystallographic structures The compound exists in three levels of hydration corresponding to different crystallographic structures and to minerals: * (anhydrite): anhydrous state. The structure is related to that of zirconium orthosilicate (zircon): is 8-coordinate, is tetrahedral, O is 3-coordinate. * (gypsum and selenite (mineral)): dihydrate. * (bassanite): hemihydrate, also known as plaster of Paris. Spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terlinguaite
Terlinguaite is the naturally occurring mineral with formula Hg2 Cl O. It is formed by the weathering of other mercury-containing minerals. It was discovered in 1900 in the Terlingua District of Brewster County Brewster County is a county located in the U.S. state of Texas. It is in West Texas and its county seat (and only city) is Alpine. It is one of the nine counties that comprise the Trans-Pecos region, and borders Mexico. Brewster County is th ..., Texas, for which it is named. Its color is yellow, greenish yellow, brown, or olive green. References Mercury minerals Halide minerals Geology of Texas Oxychlorides Monoclinic minerals Minerals in space group 15 {{halide-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Calomel
Calomel is a mercury chloride mineral with formula Hg2Cl2 (see mercury(I) chloride). The name derives from Greek ''kalos'' (beautiful) and ''melas'' (black) because it turns black on reaction with ammonia. This was known to alchemists. Calomel occurs as a secondary mineral which forms as an alteration product in mercury deposits. It occurs with native mercury, amalgam, cinnabar, mercurian tetrahedrite, eglestonite, terlinguaite, montroydite, kleinite, moschelite, kadyrelite, kuzminite, chursinite, kelyanite, calcite, limonite and various clay minerals. The type locality is Moschellandsburg, Alsenz-Obermoschel, Rhineland-Palatinate, Germany. History The substance later known as calomel was first documented in ancient Persia by medical historian Rhazes in year 850. Only a few of the compounds he mentioned could be positively identified as calomel, as not every alchemist disclosed what compounds they used in their drugs. Calomel first entered Western medical literat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corderoite
Corderoite is an extremely rare mercury sulfide chloride mineral with formula Hg3S2Cl2. It crystallizes in the isometric crystal system. It is soft, 1.5 to 2 on the Mohs scale, and varies in color from light gray to black and rarely pink or yellow. It was first described in 1974 for occurrences in the McDermitt Mercury mine in Humboldt County, Nevada. The name is from the old name of the mine, the ''Old Cordero Mine.''http://www.mindat.org/loc-4206.html Mindat McDermii Mine page Structure Corderoite has crankshaft chains that are crosswise linked by additional Hg²+. The bond distance between the cation Hg and anion S is 2.422 Angstroms. It has two angles, Hg-S-HG= 94.1º and S-Hg-S= 165.1º. Various sulfide halides of Hg share the feature of being face-sharing gS2X4−6 polyhedral, as corderoite's polyhedra X=Cl. Geologic occurrence The main occurrence of corderoite in the type locality is in the Upper Miocene playa sediments within a thick zone, around , sub parallel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vermilion
Vermilion (sometimes vermillion) is a color, color family, and pigment most often made, since antiquity until the 19th century, from the powdered mineral cinnabar (a form of mercury sulfide, which is toxic) and its corresponding color. It is very often synonymous with red orange, which often takes a modern form just 11% brighter (at full brightness). Etymology and orthography The word vermilion came from the Old French word ''vermeillon'', which was derived from ''vermeil'', from the Latin ''vermiculus'', the diminutive of the Latin word ''vermis'', or worm. The name originated because it had a similar color to the natural red dye made from an insect, '' Kermes vermilio'', which was widely used in Europe. The first recorded use of "vermilion" as a color name in English was in 1289. The term cinnabar was used interchangeably with vermilion until the 17th century, when vermilion became the more common name. Now the term "cinnabar" is used in mineralogy and crystallography f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cinnabar09
Cinnabar (), or cinnabarite (), from the grc, κιννάβαρι (), is the bright scarlet to brick-red form of mercury(II) sulfide (HgS). It is the most common source ore for refining elemental mercury and is the historic source for the brilliant red or scarlet pigment termed vermilion and associated red mercury pigments. Cinnabar generally occurs as a vein-filling mineral associated with recent volcanic activity and alkaline hot springs. The mineral resembles quartz in symmetry and in its exhibiting birefringence. Cinnabar has a mean refractive index near 3.2, a hardness between 2.0 and 2.5, and a specific gravity of approximately 8.1. The color and properties derive from a structure that is a hexagonal crystalline lattice belonging to the trigonal crystal system, crystals that sometimes exhibit twinning. Cinnabar has been used for its color since antiquity in the Near East, including as a rouge-type cosmetic, in the New World since the Olmec culture, and in China since ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymorphism (materials Science)
In materials science, polymorphism describes the existence of a solid material in more than one form or crystal structure. Polymorphism is a form of isomerism. Any crystalline material can exhibit the phenomenon. Allotropy refers to polymorphism for chemical elements. Polymorphism is of practical relevance to pharmaceuticals, agrochemicals, pigments, dyestuffs, foods, and explosives. According to IUPAC, a polymorphic transition is "A reversible transition of a solid crystalline phase at a certain temperature and pressure (the inversion point) to another phase of the same chemical composition with a different crystal structure." According to McCrone, polymorphs are "different in crystal structure but identical in the liquid or vapor states." Materials with two polymorphs are called dimorphic, with three polymorphs, trimorphic, etc. Examples Many compounds exhibit polymorphism. It has been claimed that "every compound has different polymorphic forms, and that, in general, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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