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Azurite Crystal Structure
Azurite is a soft, deep-blue copper mineral produced by weathering of copper ore deposits. During the early 19th century, it was also known as chessylite, after the type locality at Chessy-les-Mines near Lyon, France. The mineral, a basic carbonate with the chemical formula Cu3(CO3)2(OH)2, has been known since ancient times, and was mentioned in Pliny the Elder's '' Natural History'' under the Greek name (κυανός: "deep blue," root of English ''cyan'') and the Latin name ''caeruleum''. Since antiquity, azurite's exceptionally deep and clear blue has been associated with low-humidity desert and winter skies. The modern English name of the mineral reflects this association, since both ''azurite'' and ''azure'' are derived via Arabic from the Persian (لاژورد), an area known for its deposits of another deep-blue stone, lapis lazuli ("stone of azure"). Mineralogy Azurite has the formula Cu3(CO3)2(OH)2, with the copper(II) cations linked to two different anions, carbona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carbonate Mineral
Carbonate minerals are those minerals containing the carbonate ion, . Carbonate divisions Anhydrous carbonates *Calcite group: trigonal ** Calcite CaCO3 ** Gaspéite (Ni,Mg,Fe2+)CO3 **Magnesite MgCO3 ** Otavite CdCO3 ** Rhodochrosite MnCO3 ** Siderite FeCO3 ** Smithsonite ZnCO3 **Spherocobaltite CoCO3 *Aragonite group: orthorhombic ** Aragonite CaCO3 ** Cerussite PbCO3 ** Strontianite SrCO3 ** Witherite BaCO3 ** Rutherfordine UO2CO3 ** Natrite Na2CO3 Anhydrous carbonates with compound formulas *Dolomite group: trigonal ** Ankerite CaFe(CO3)2 ** Dolomite CaMg(CO3)2 ** Huntite Mg3Ca(CO3)4 ** Minrecordite CaZn(CO3)2 ** Barytocalcite BaCa(CO3)2 Carbonates with hydroxyl or halogen *Carbonate with hydroxide: monoclinic **Azurite Cu3(CO3)2(OH)2 ** Hydrocerussite Pb3(CO3)2(OH)2 ** Malachite Cu2CO3(OH)2 ** Rosasite (Cu,Zn)2CO3(OH)2 ** Phosgenite Pb2(CO3)Cl2 ** Hydrozincite Zn5(CO3)2(OH)6 ** Aurichalcite (Zn,Cu)5(CO3)2(OH)6 Hydrated carbonates * Hydromagnesite Mg5(CO3)4(OH)2.4H2O ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Azurite Crystal Structure
Azurite is a soft, deep-blue copper mineral produced by weathering of copper ore deposits. During the early 19th century, it was also known as chessylite, after the type locality at Chessy-les-Mines near Lyon, France. The mineral, a basic carbonate with the chemical formula Cu3(CO3)2(OH)2, has been known since ancient times, and was mentioned in Pliny the Elder's '' Natural History'' under the Greek name (κυανός: "deep blue," root of English ''cyan'') and the Latin name ''caeruleum''. Since antiquity, azurite's exceptionally deep and clear blue has been associated with low-humidity desert and winter skies. The modern English name of the mineral reflects this association, since both ''azurite'' and ''azure'' are derived via Arabic from the Persian (لاژورد), an area known for its deposits of another deep-blue stone, lapis lazuli ("stone of azure"). Mineralogy Azurite has the formula Cu3(CO3)2(OH)2, with the copper(II) cations linked to two different anions, carbona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crystal Field Theory
Crystal field theory (CFT) describes the breaking of degeneracies of electron orbital states, usually ''d'' or ''f'' orbitals, due to a static electric field produced by a surrounding charge distribution (anion neighbors). This theory has been used to describe various spectroscopies of transition metal coordination complexes, in particular optical spectra (colors). CFT successfully accounts for some magnetic properties, colors, hydration enthalpies, and spinel structures of transition metal complexes, but it does not attempt to describe bonding. CFT was developed by physicists Hans Bethe and John Hasbrouck van Vleck in the 1930s. CFT was subsequently combined with molecular orbital theory to form the more realistic and complex ligand field theory (LFT), which delivers insight into the process of chemical bonding in transition metal complexes. Overview of crystal field theory According to crystal field theory, the interaction between a transition metal and ligands arises from th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coordination Complex
A coordination complex consists of a central atom or ion, which is usually metallic and is called the ''coordination centre'', and a surrounding array of bound molecules or ions, that are in turn known as ''ligands'' or complexing agents. Many metal-containing compounds, especially those that include transition metals (elements like titanium that belong to the Periodic Table's d-block), are coordination complexes. Nomenclature and terminology Coordination complexes are so pervasive that their structures and reactions are described in many ways, sometimes confusingly. The atom within a ligand that is bonded to the central metal atom or ion is called the donor atom. In a typical complex, a metal ion is bonded to several donor atoms, which can be the same or different. A polydentate (multiple bonded) ligand is a molecule or ion that bonds to the central atom through several of the ligand's atoms; ligands with 2, 3, 4 or even 6 bonds to the central atom are common. These compl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Gravity
Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water (molecule), water at its densest (at ); for gases, the reference is air at room temperature (). The term "relative density" (often abbreviated r.d. or RD) is often preferred in scientific usage, whereas the term "specific gravity" is deprecation, deprecated. If a substance's relative density is less than 1 then it is less dense than the reference; if greater than 1 then it is denser than the reference. If the relative density is exactly 1 then the densities are equal; that is, equal volumes of the two substances have the same mass. If the reference material is water, then a substance with a relative density (or specific gravity) less than 1 will float in water. For example, an ice cube, with a relative density of about 0.91, will float. A substance wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mohs Hardness
The Mohs scale of mineral hardness () is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material. The scale was introduced in 1812 by the German geologist and mineralogist Friedrich Mohs, in his book ''"Versuch einer Elementar-Methode zur naturhistorischen Bestimmung und Erkennung der Fossilien"''; it is one of several definitions of hardness in materials science, some of which are more quantitative. The method of comparing hardness by observing which minerals can scratch others is of great antiquity, having been mentioned by Theophrastus in his treatise ''On Stones'', , followed by Pliny the Elder in his '' Naturalis Historia'', . The Mohs scale is useful for identification of minerals in the field, but is not an accurate predictor of how well materials endure in an industrial setting – ''toughness''. Minerals The Mohs scale of mineral hardness is based on the abilit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Druse (geology)
In geology, druse refers to a coating of fine crystals on a rock fracture surface or vein or within a vug or geode. See also * Crystal habit * Miarolitic cavity Miarolitic cavities (or ''miarolitic texture'') are typically crystal-lined irregular cavities or vugs most commonly found in granitic pegmatites, and also in a variety of igneous rocks. The central portions of pegmatites are often miarolitic as ... References Mineral habits {{petrology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclinic System
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic system. They form a parallelogram prism. Hence two pairs of vectors are perpendicular (meet at right angles), while the third pair makes an angle other than 90°. Bravais lattices Two monoclinic Bravais lattices exist: the primitive monoclinic and the base-centered monoclinic. For the base-centered monoclinic lattice, the primitive cell has the shape of an oblique rhombic prism;See , row mC, column Primitive, where the cell parameters are given as a1 = a2, α = β it can be constructed because the two-dimensional centered rectangular base layer can also be described with primitive rhombic axes. Note that the length a of the primitive cell below equals \frac \sqrt of the conventional cell above. Crystal classes The table below organiz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper(II) Carbonate
Copper(II) carbonate or cupric carbonate is a chemical compound with formula . At ambient temperatures, it is an ionic solid (a salt) consisting of copper(II) cations and carbonate anions . This compound is rarely encountered because it is difficult to prepare and readily reacts with water moisture from the air. The terms "copper carbonate", "copper(II) carbonate", and "cupric carbonate" almost always refer (even in chemistry texts) to a basic copper carbonate (or copper(II) carbonate hydroxide), such as ()2 (which occurs naturally as the mineral malachite) or ()2()2 (azurite). For this reason, the qualifier neutral may be used instead of "basic" to refer specifically to . Preparation Reactions that may be expected to yield , such as mixing solutions of copper(II) sulfate and sodium carbonate in ambient conditions, yield instead a basic carbonate and , due to the great affinity of the ion for the hydroxide anion . Thermal decomposition of the basic carbonate at atmosph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zinc
Zinc is a chemical element with the symbol Zn and atomic number 30. Zinc is a slightly brittle metal at room temperature and has a shiny-greyish appearance when oxidation is removed. It is the first element in group 12 (IIB) of the periodic table. In some respects, zinc is chemically similar to magnesium: both elements exhibit only one normal oxidation state (+2), and the Zn2+ and Mg2+ ions are of similar size.The elements are from different metal groups. See periodic table. Zinc is the 24th most abundant element in Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest workable lodes are in Australia, Asia, and the United States. Zinc is refined by froth flotation of the ore, roasting, and final extraction using electricity ( electrowinning). Zinc is an essential trace element for humans, animals, plants and for microorganisms and is necessary for prenatal and postnatal development. It ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aurichalcite
Aurichalcite is a carbonate mineral, usually found as a secondary mineral in copper and zinc deposits. Its chemical formula is . The zinc to copper ratio is about 5:4. Occurrence Aurichalcite typically occurs in the oxidized zone of copper and zinc deposits. Associated minerals include: rosasite, smithsonite, hemimorphite, hydrozincite, malachite and azurite. It was first described in 1839 by Bottger who named the mineral for its zinc and copper content after the Greek ''όρειχαλκος'', for "mountain brass" or "mountain copper", the name of '' orichalcum'', a fabulous metal, mentioned in the legend of the mythic lost continent Atlantis. The type locality is the Loktevskoye Mine, Upper Loktevka River, Rudnyi Altai, Altaiskii Krai, Western Siberia, Russia. Crystallography Aurichalcite displays prismatic An optical prism is a transparent optical element with flat, polished surfaces that are designed to refract light. At least one surface must be angled — e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Malachite
Malachite is a copper carbonate hydroxide mineral, with the formula Cu2CO3(OH)2. This opaque, green-banded mineral crystallizes in the monoclinic crystal system, and most often forms botryoidal, fibrous, or stalagmitic masses, in fractures and deep, underground spaces, where the water table and hydrothermal fluids provide the means for chemical precipitation. Individual crystals are rare, but occur as slender to acicular prisms. Pseudomorphs after more tabular or blocky azurite crystals also occur. Etymology and history The stone's name derives (via la, molochītis, frm, melochite, and Middle English ''melochites'') from Greek Μολοχίτης λίθος ''molochites lithos'', "mallow-green stone", from μολόχη ''molochē'', variant of μαλάχη ''malāchē'', "mallow". The mineral was given this name due to its resemblance to the leaves of the mallow plant. Malachite was mined from deposits near the Isthmus of Suez and the Sinai as early as 4000 BCE. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
