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37-534: Dolomite may refer to: Dolomite (mineral) , a carbonate mineral Dolomite (rock) , also known as dolostone, a sedimentary carbonate rock Dolomite, Alabama , United States, an unincorporated community Dolomite, California , United States, an unincorporated community Dolomites , a section of the Alps Lucanian Dolomites , a mountain range in southern Italy Triumph Dolomite (1934–1940) ,

74-492: A 1999 in-name-only sequel to Dolemite "Dolemite", the opening track on Tore Down House , a 1997 album by Scott Henderson; the track features samples from the film Dolemite Is My Name , 2019 American biographical comedy film Dolomiten , a German-language newspaper published in South Tyrol, Italy Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with

111-466: A more stable phase (such as partially ordered dolomite) during periodical intervals of dissolution and re-precipitation. The general principle governing the course of this irreversible geochemical reaction has been coined "breaking Ostwald's step rule ". High diagenetic temperatures, such as those of groundwater flowing along deeply rooted fault systems affecting some sedimentary successions or deeply buried limestone rocks allocate dolomitization . But

148-492: A pH buffer and as a magnesium source. Pastures can be limed with dolomitic lime to raise their pH and where there is a magnesium deficiency. Dolomite is also used as the substrate in marine (saltwater) aquariums to help buffer changes in the pH of the water. Calcined dolomite is also used as a catalyst for destruction of tar in the gasification of biomass at high temperature. Particle physics researchers like to build particle detectors under layers of dolomite to enable

185-485: A physical mixture of the two is referred to as sylvinite . Because minerals are natural materials they are prone to large variations in composition. In many cases specimens are members for a solid solution family and geologists find it more helpful to discuss the composition of the family than an individual specimen. Olivine is described by the formula (Mg, Fe) 2 SiO 4 , which is equivalent to (Mg 1−x Fe x ) 2 SiO 4 . The ratio of magnesium to iron varies between

222-413: A solid solution at all relative concentrations of the two species. In this case, the pure phase of each element is of the same crystal structure, and the similar properties of the two elements allow for unbiased substitution through the full range of relative concentrations. Solid solution of pseudo-binary systems in complex systems with three or more components may require a more involved representation of

259-513: A solid solution becomes unstable—due to a lower temperature, for example—exsolution occurs and the two phases separate into distinct microscopic to megascopic lamellae . This is mainly caused by difference in cation size. Cations which have a large difference in radii are not likely to readily substitute. Alkali feldspar minerals , for example, have end members of albite , NaAlSi 3 O 8 and microcline , KAlSi 3 O 8 . At high temperatures Na and K readily substitute for each other and so

296-469: A solid solution is a complicated matter involving the chemical , crystallographic , and quantum properties of the substances in question. Substitutional solid solutions, in accordance with the Hume-Rothery rules , may form if the solute and solvent have: a solid solution mixes with others to form a new solution The phase diagram in the above diagram displays an alloy of two metals which forms

333-591: A sporting car made by Triumph Motor Company Triumph Dolomite , a small car made by the British Leyland Corporation in the 1970s and 1980s Manila Bay Beach , informally known as "Dolomite Beach", an urban artificial beach in Manila, Philippines See also [ edit ] Dolemite , 1975 blaxploitation feature film and the name of its principal character Shaolin Dolemite ,

370-406: A unique phase". The definition "crystal containing a second constituent which fits into and is distributed in the lattice of the host crystal" given in refs., is not general and, thus, is not recommended. The expression is to be used to describe a solid phase containing more than one substance when, for convenience, one (or more) of the substances, called the solvent, is treated differently from

407-413: Is not a solid solution. Instead, an examination of the microstructure of a mixture in this range would reveal two phases—solid solution A {\displaystyle A} -in- B {\displaystyle B} and solid solution B {\displaystyle B} -in- A {\displaystyle A} would form separate phases, perhaps lamella or grains . In

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444-465: Is an abundant rock-forming mineral are important as aquifers and contribute to karst terrain formation. Modern dolomite formation has been found to occur under anaerobic conditions in supersaturated saline lagoons such as those at the Rio de Janeiro coast of Brazil , namely, Lagoa Vermelha and Brejo do Espinho. There are many other localities where modern dolomite forms, notably along sabkhas in

481-530: Is an important petroleum reservoir rock, and serves as the host rock for large strata-bound Mississippi Valley-Type (MVT) ore deposits of base metals such as lead , zinc , and copper . Where calcite limestone is uncommon or too costly, dolomite is sometimes used in its place as a flux for the smelting of iron and steel. Large quantities of processed dolomite are used in the production of float glass . In horticulture , dolomite and dolomitic limestone are added to soils and soilless potting mixes as

518-502: Is likely result from complexation of both magnesium and calcium by carboxylic acids comprising EPS. Vast deposits of dolomite are present in the geological record, but the mineral is relatively rare in modern environments. Reproducible, inorganic low-temperature syntheses of dolomite are yet to be performed. Usually, the initial inorganic precipitation of a metastable "precursor" (such as magnesium calcite) can easily be achieved. The precursor phase will theoretically change gradually into

555-460: Is often applied to the case of mixtures of drug and polymer . The number of drug molecules that do behave as solvent (plasticizer) of polymers is small. On a phase diagram a solid solution is represented by an area, often labeled with the structure type, which covers the compositional and temperature/pressure ranges. Where the end members are not isostructural there are likely to be two solid solution ranges with different structures dictated by

592-546: The Persian Gulf , but also in sedimentary basins bearing gas hydrates and hypersaline lakes. It is often thought that dolomite nucleates with the help of sulfate-reducing bacteria (e.g. Desulfovibrio brasiliensis ), but other microbial metabolisms have been also found to mediate in dolomite formation. In general, low-temperature dolomite may occur in natural supersaturated environments rich in extracellular polymeric substances (EPS) and microbial cell surfaces. This

629-538: The iron -dominant ankerite and the manganese -dominant kutnohorite . Small amounts of iron in the structure give the crystals a yellow to brown tint. Manganese substitutes in the structure also up to about three percent MnO. A high manganese content gives the crystals a rosy pink color. Lead , zinc , and cobalt also can substitute in the structure for magnesium. The mineral dolomite is closely related to huntite Mg 3 Ca(CO 3 ) 4 . Because dolomite can be dissolved by slightly acidic water, areas where dolomite

666-401: The trigonal-rhombohedral system. It forms white, tan, gray, or pink crystals. Dolomite is a double carbonate, having an alternating structural arrangement of calcium and magnesium ions. Unless it is in fine powder form, it does not rapidly dissolve or effervesce (fizz) in cold dilute hydrochloric acid as calcite does. Crystal twinning is common. Solid solution exists between dolomite,

703-428: The above diagram shows the phases of a mixture of two substances in varying concentrations, A {\displaystyle A} and B {\displaystyle B} . The region labeled " α {\displaystyle \alpha } " is a solid solution, with B {\displaystyle B} acting as the solute in a matrix of A {\displaystyle A} . On

740-486: The atomic radii of the solute atom is larger than the solvent atom it replaces the crystal structure ( unit cell ) often expands to accommodate it, this means that the composition of a material in a solid solution can be calculated from the unit cell volume a relationship known as Vegard's law . Some mixtures will readily form solid solutions over a range of concentrations, while other mixtures will not form solid solutions at all. The propensity for any two substances to form

777-438: The crystalline phase consists of two (non-charged) organic molecules the line phase is commonly known as a cocrystal . In metallurgy alloys with a set composition are referred to as intermetallic compounds. A solid solution is likely to exist when the two elements (generally metals ) involved are close together on the periodic table , an intermetallic compound generally results when two metals involved are not near each other on

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814-428: The detectors to detect the highest possible number of exotic particles. Because dolomite contains relatively minor quantities of radioactive materials, it can insulate against interference from cosmic rays without adding to background radiation levels. In addition to being an industrial mineral, dolomite is highly valued by collectors and museums when it forms large, transparent crystals. The specimens that appear in

851-473: The intimate mixing of components at the atomic level and distinguishes these homogeneous materials from physical mixtures of components. Two terms are mainly associated with solid solutions – solvents and solutes, depending on the relative abundance of the atomic species. In general if two compounds are isostructural then a solid solution will exist between the end members (also known as parents). For example sodium chloride and potassium chloride have

888-467: The magnesite quarry exploited in Eugui, Esteribar, Navarra (Spain) are considered among the best in the world. Solid solution A solid solution, a term popularly used for metals, is a homogeneous mixture of two compounds in solid state and having a single crystal structure . Many examples can be found in metallurgy , geology , and solid-state chemistry . The word "solution" is used to describe

925-590: The mineral dolomite was probably first described by Carl Linnaeus in 1768. In 1791, it was described as a rock by the French naturalist and geologist Déodat Gratet de Dolomieu (1750–1801), first in buildings of the old city of Rome, and later as samples collected in the Tyrolean Alps . Nicolas-Théodore de Saussure first named the mineral (after Dolomieu) in March 1792. The mineral dolomite crystallizes in

962-471: The mineral is also volumetrically important in some Neogene platforms never subjected to elevated temperatures. Under such conditions of diagenesis the long-term activity of the deep biosphere could play a key role in dolomitization, since diagenetic fluids of contrasting composition are mixed as a response to Milankovitch cycles . A recent biotic synthetic experiment claims to have precipitated ordered dolomite when anoxygenic photosynthesis proceeds in

999-591: The other end of the concentration scale, the region labeled " β {\displaystyle \beta } " is also a solid solution, with A {\displaystyle A} acting as the solute in a matrix of B {\displaystyle B} . The large solid region in between the α {\displaystyle \alpha } and β {\displaystyle \beta } solid solutions, labeled " α {\displaystyle \alpha } + β {\displaystyle \beta } ",

1036-401: The other substances, called solutes. One or several of the components can be macromolecules . Some of the other components can then act as plasticizers, i.e., as molecularly dispersed substances that decrease the glass-transition temperature at which the amorphous phase of a polymer is converted between glassy and rubbery states. In pharmaceutical preparations, the concept of solid solution

1073-429: The parents. In this case the ranges may overlap and the materials in this region can have either structure, or there may be a miscibility gap in solid state indicating that attempts to generate materials with this composition will result in mixtures. In areas on a phase diagram which are not covered by a solid solution there may be line phases, these are compounds with a known crystal structure and set stoichiometry. Where

1110-427: The periodic table. The solute may incorporate into the solvent crystal lattice substitutionally , by replacing a solvent particle in the lattice, or interstitially , by fitting into the space between solvent particles. Both of these types of solid solution affect the properties of the material by distorting the crystal lattice and disrupting the physical and electrical homogeneity of the solvent material. Where

1147-423: The phase diagram with more than one solvus curves drawn corresponding to different equilibrium chemical conditions. Solid solutions have important commercial and industrial applications, as such mixtures often have superior properties to pure materials. Many metal alloys are solid solutions. Even small amounts of solute can affect the electrical and physical properties of the solvent. The binary phase diagram in

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1184-541: The phase diagram, at three different concentrations, the material will be solid until heated to its melting point , and then (after adding the heat of fusion ) become liquid at that same temperature: At other proportions, the material will enter a mushy or pasty phase until it warms up to being completely melted. The mixture at the dip point of the diagram is called a eutectic alloy. Lead-tin mixtures formulated at that point (37/63 mixture) are useful when soldering electronic components, particularly if done manually, since

1221-456: The presence of manganese(II). A still perplexing example of an organogenic origin is that of the reported formation of dolomite in the urinary bladder of a Dalmatian dog, possibly as the result of an illness or infection. Dolomite is used as an ornamental stone, a concrete aggregate, and a source of magnesium oxide , as well as in the Pidgeon process for the production of magnesium . It

1258-432: The same cubic crystal structure so it is possible to make a pure compound with any ratio of sodium to potassium (Na 1-x K x )Cl by dissolving that ratio of NaCl and KCl in water and then evaporating the solution. A member of this family is sold under the brand name Lo Salt which is (Na 0.33 K 0.66 )Cl, hence it contains 66% less sodium than normal table salt (NaCl). The pure minerals are called halite and sylvite ;

1295-409: The solid phase is quickly entered as the solder cools. In contrast, when lead-tin mixtures were used to solder seams in automobile bodies a pasty state enabled a shape to be formed with a wooden paddle or tool, so a 70–30 lead to tin ratio was used. (Lead is being removed from such applications owing to its toxicity and consequent difficulty in recycling devices and components that include lead.) When

1332-535: The title Dolomite . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Dolomite&oldid=1188883231 " Categories : Disambiguation pages Place name disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Dolomite (mineral) As stated by Nicolas-Théodore de Saussure

1369-418: The two endmembers of the solid solution series: forsterite (Mg-endmember: Mg 2 SiO 4 ) and fayalite (Fe-endmember: Fe 2 SiO 4 ) but the ratio in olivine is not normally defined. With increasingly complex compositions the geological notation becomes significantly easier to manage than the chemical notation. The IUPAC definition of a solid solution is a "solid in which components are compatible and form

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