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Ilmenite
Ilmenite is a titanium-iron oxide mineral with the idealized formula . It is a weakly magnetic black or steel-gray solid. Ilmenite is the most important ore of titanium and the main source of titanium dioxide, which is used in paints, printing inks, fabrics, plastics, paper, sunscreen, food and cosmetics. Structure and properties Ilmenite is a heavy (specific gravity 4.7), moderately hard (Mohs hardness 5.6 to 6), opaque black mineral with a submetallic luster. It is almost always massive, with thick tabular crystals being quite rare. It shows no discernible cleavage, breaking instead with a conchoidal to uneven fracture. Ilmenite crystallizes in the trigonal system with space group ''R''. The ilmenite crystal structure consists of an ordered derivative of the corundum structure; in corundum all cations are identical but in ilmenite Fe2+ and Ti4+ ions occupy alternating layers perpendicular to the trigonal c axis. Pure ilmenite is paramagnetic (showing only very weak ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanium Dioxide
Titanium dioxide, also known as titanium(IV) oxide or titania , is the inorganic compound derived from titanium with the chemical formula . When used as a pigment, it is called titanium white, Pigment White 6 (PW6), or Colour Index International, CI 77891. It is a white solid that is insoluble in water, although mineral forms can appear black. As a pigment, it has a wide range of applications, including paint, sunscreen, and food coloring. When used as a food coloring, it has E number E171. World production in 2014 exceeded 9 million tonnes. It has been estimated that titanium dioxide is used in two-thirds of all pigments, and pigments based on the oxide have been valued at a price of $13.2 billion. Structure In all three of its main dioxides, titanium exhibits Octahedral molecular geometry, octahedral geometry, being bonded to six oxide anions. The oxides in turn are bonded to three Ti centers. The overall crystal structures of rutile and anatase are tetragonal in symmetry ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Titanium
Titanium is a chemical element; it has symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in sea water, aqua regia, and chlorine. Titanium was discovered in Cornwall, Great Britain, by William Gregor in 1791 and was named by Martin Heinrich Klaproth after the Titans of Greek mythology. The element occurs within a number of minerals, principally rutile and ilmenite, which are widely distributed in the Earth's crust and lithosphere; it is found in almost all living things, as well as bodies of water, rocks, and soils. The metal is extracted from its principal mineral ores by the Kroll and Hunter processes. The most common compound, titanium dioxide (TiO2), is a popular photocatalyst and is used in the manufacture of white pigments. Other compounds include titanium tetrachloride (TiCl4), a component of smoke screens and cata ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kimberlite
Kimberlite is an igneous rock and a rare variant of peridotite. It is most commonly known as the main host matrix for diamonds. It is named after the town of Kimberley, Northern Cape, Kimberley in South Africa, where the discovery of an 83.5-Carat (mass), carat (16.70 g) diamond called the Star of South Africa (diamond), Star of South Africa in 1869 spawned a diamond rush and led to the excavation of the open-pit mine called the Big Hole. Previously, the term kimberlite has been applied to olivine lamproites as Kimberlite II, however this has been in error. Kimberlite occurs in the Earth's Crust (geology), crust in vertical structures known as Volcanic pipe, kimberlite pipes, as well as igneous Dike (geology), dykes and can also occur as horizontal Sill (geology), sills. Kimberlite pipes are the most important source of mined diamonds today. The consensus on kimberlites is that they are formed deep within Earth's mantle. Formation occurs at depths between 150 and 450 kilometres ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heavy Mineral Sands Ore Deposits
Heavy mineral sands are a class of ore deposit which is an important source of zirconium, titanium, thorium, tungsten, rare-earth elements, the industrial minerals diamond, sapphire, garnet, and occasionally precious metals or gemstones. Heavy mineral sands are placer deposits formed most usually in beach environments by concentration due to the specific gravity of the mineral grains. It is equally likely that some concentrations of heavy minerals (aside from the usual gold placers) exist within streambeds, but most are of a low grade and are relatively small. Grade and tonnage distribution The grade of a typical heavy mineral sand ore deposit is usually low. Within the 21st century, the lowest cut-off grades of heavy minerals, as a total heavy mineral (THM) concentrate from the bulk sand, in most ore deposits of this type is around 1% heavy minerals, although several are higher grade. Of this total heavy mineral concentrate (THM), the components are typically * Z ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geikielite
Geikielite is a magnesium titanium oxide mineral with formula: MgTiO3. It is a member of the ilmenite group. It crystallizes in the trigonal system forming typically opaque, black to reddish black crystals. It was first described in 1892 for an occurrence in the Ceylonese gem bearing gravel placers. It was named for Scottish geologist Sir Archibald Geikie (1835–1924). It occurs in metamorphosed impure magnesian limestones, in serpentinite derived from ultramafic rocks, in kimberlites and carbonatites. Associated minerals include rutile, spinel, clinohumite, perovskite, diopside, serpentine, forsterite, brucite, hydrotalcite, chlorite and calcite Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a component of limestone. Calcite defines hardness 3 on .... References Further reading * * * * * * * * Titanium minerals Magnesium m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnetite
Magnetite is a mineral and one of the main iron ores, with the chemical formula . It is one of the iron oxide, oxides of iron, and is ferrimagnetism, ferrimagnetic; it is attracted to a magnet and can be magnetization, magnetized to become a permanent magnet itself. With the exception of extremely rare native iron deposits, it is the most magnetic of all the naturally occurring minerals on Earth. Naturally magnetized pieces of magnetite, called lodestone, will attract small pieces of iron, which is how ancient peoples first discovered the property of magnetism. Magnetite is black or brownish-black with a metallic luster, has a Mohs scale of mineral hardness, Mohs hardness of 5–6 and leaves a black streak (mineralogy), streak. Small grains of magnetite are very common in igneous rocks, igneous and metamorphic rocks. The chemical IUPAC name is iron(II,III) oxide and the common chemical name is ''ferrous-ferric oxide''. Properties In addition to igneous rocks, magnetite als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyrophanite
Pyrophanite is a manganese titanium oxide mineral with formula: MnTiO3. It is a member of the ilmenite group. It is a deep red to greenish black mineral which crystallizes in the trigonal system. Discovery and occurrence It was first described in 1890 from an occurrence in the Harstigen Mine, Filipstad, Värmland, Sweden. Its name was derived from the Greek ''πΰρ,'' fire, and ''φαίνεσθαι,'' to appear, because of the deep red color of the mineral. Its main occurrence is in manganese deposits that have undergone metamorphism. It also occurs in granite, amphibolite and serpentinite as an uncommon accessory mineral. Associated minerals include ilmenite, geikielite, hematite, spinel, gahnite, chromite, magnetite, ganophyllite, manganophyllite, hendricksite, garnet and calcite Calcite is a Carbonate minerals, carbonate mineral and the most stable Polymorphism (materials science), polymorph of calcium carbonate (CaCO3). It is a very common mineral, particularly as a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leucoxene
Leucoxene is a fine granular alteration product of titanium minerals. It varies in color from yellow to brown. It consists mainly of rutile or anatase. It is observed in some igneous rocks and iron ore deposits as the result of the alteration of ilmenite, perovskite, or titanite Titanite, or sphene (), is a calcium titanium nesosilicate mineral, Ca Ti Si O5. Trace impurities of iron and aluminium are typically present. Also commonly present are rare earth metals including cerium and yttrium; calcium may be partly rep .... References * Hurlbut, Cornelius S.; Klein, Cornelis, 1985, Manual of Mineralogy, 20th ed., Mindat.org Oxide minerals {{oxide-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manaccan
Manaccan (; ) is a civil parishes in England, civil parish and village on the The Lizard, Lizard peninsula in south Cornwall, England, United Kingdom. The village is about five miles (8 km) south-southwest of Falmouth, Cornwall, Falmouth. The origin of the name Manaccan is probably derived not from a saint but from the Cornish for (church) of the monks. It was also at times called Minster in English because it must once have had a Celtic monastery. "Mannacus, St Manacca" is recorded as the patron saint as early as 1308. The population of Manaccan was 321 in the 2011 census, an increase from 299 in the 2001 census. Manaccan lies within the Cornwall Area of Outstanding Natural Beauty (AONB). Almost a third of Cornwall has AONB designation, with the same status and protection as a National parks of England and Wales, National Park. Governance Manaccan is in the United Kingdom Parliament constituencies, parliamentary constituency of St Ives (UK Parliament constituency), St ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigonal
In crystallography, the hexagonal crystal family is one of the six crystal family, crystal families, which includes two crystal systems (hexagonal and trigonal) and two lattice systems (hexagonal and rhombohedral). While commonly confused, the trigonal crystal system and the rhombohedral lattice system are not equivalent (see section hexagonal crystal family#Crystal systems, crystal systems below). In particular, there are crystals that have trigonal symmetry but belong to the hexagonal lattice (such as α-quartz). The hexagonal crystal family consists of the 12 point groups such that at least one of their space groups has the hexagonal lattice as underlying lattice, and is the union of the hexagonal crystal system and the trigonal crystal system. There are 52 space groups associated with it, which are exactly those whose Bravais lattice is either hexagonal or rhombohedral. __TOC__ Lattice systems The hexagonal crystal family consists of two lattice systems: hexagonal and rhom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metasomatism
Metasomatism (from the Greek μετά ''metá'' "change" and σῶμα ''sôma'' "body") is the chemical alteration of a rock by hydrothermal and other fluids. It is traditionally defined as metamorphism which involves a change in the chemical composition, excluding volatile components. It is the replacement of one rock by another of different mineralogical and chemical composition. The minerals which compose the rocks are dissolved and new mineral formations are deposited in their place. Dissolution and deposition occur simultaneously and the rock remains solid. Synonyms of the word ''metasomatism'' are metasomatosis and metasomatic process. The word ''metasomatose'' can be used as a name for specific varieties of metasomatism (for example '' Mg-metasomatose'' and '' Na-metasomatose''). Metasomatism can occur via the action of hydrothermal fluids from an igneous or metamorphic source. In the igneous environment, metasomatism produces skarns, greisen, and may affect hornfel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigonal
In crystallography, the hexagonal crystal family is one of the six crystal family, crystal families, which includes two crystal systems (hexagonal and trigonal) and two lattice systems (hexagonal and rhombohedral). While commonly confused, the trigonal crystal system and the rhombohedral lattice system are not equivalent (see section hexagonal crystal family#Crystal systems, crystal systems below). In particular, there are crystals that have trigonal symmetry but belong to the hexagonal lattice (such as α-quartz). The hexagonal crystal family consists of the 12 point groups such that at least one of their space groups has the hexagonal lattice as underlying lattice, and is the union of the hexagonal crystal system and the trigonal crystal system. There are 52 space groups associated with it, which are exactly those whose Bravais lattice is either hexagonal or rhombohedral. __TOC__ Lattice systems The hexagonal crystal family consists of two lattice systems: hexagonal and rhom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
