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Lópezite
Lópezite is a rare red chromate mineral with chemical formula: K2 Cr2 O7. It crystallizes in the triclinic crystal system. It occurs as rare vug fillings in nitrate ores in association with tarapacáite (K2CrO4), dietzeite and ulexite in the Chilean Atacama and is reported from the Bushveld igneous complex of South Africa. Lópezite was first described in 1937 for an occurrence in Iquique Province, Chile and named after Chilean mining engineer Emiliano López Saa (1871–1959). Most commercially available lópezite is artificially produced. Synthetic varieties also exhibit monoclinic 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 s ... crystals.Richard V. Gaines, H. Catherine W. Skinner, Eugene E. Foord, Brian Mason, and Abraham Rosenzweig: " Dana's new mineralogy", p. 692. J ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sulfate Minerals
The sulfate minerals are a class of minerals that include the sulfate ion () within their structure. The sulfate minerals occur commonly in primary evaporite depositional environments, as gangue minerals in hydrothermal Vein (geology), veins and as secondary minerals in the Redox, oxidizing zone of sulfide mineral deposits. The Chromate ion, chromate and manganate minerals have a similar structure and are often included with the sulfates in mineral classification systems.Klein, Cornelis and Cornelius S. Hurlbut, 1985, ''Manual of Mineralogy,'' 20th ed., John Wiley and Sons, New York, pp. 347–354 . Sulfate minerals include: *Anhydrous sulfates **Barite BaSO4 **Celestite SrSO4 **Anglesite PbSO4 **Anhydrite CaSO4 **Hanksite Na22K(SO4)9(CO3)2Cl *Hydroxide and hydrous sulfates **Gypsum CaSO4·2H2O **Chalcanthite CuSO4·5H2O **Kieserite MgSO4·H2O **Starkeyite MgSO4·4H2O **Hexahydrite MgSO4·6H2O **Epsomite MgSO4·7H2O **Meridianiite MgSO4·11H2O **Melanterite FeSO4·7H2O **Antlerite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ulexite
Ulexite (NaCaB5O6(OH)6·5H2O, hydrated sodium calcium borate hydroxide), sometimes known as TV rock or Television stone, is a mineral occurring in silky white rounded crystalline masses or in parallel fibers. The natural fibers of ulexite conduct light along their long axes, by internal reflection. Ulexite was named for the German chemist Georg Ludwig Ulex (1811–1883) who first discovered it. Ulexite is a structurally complex mineral, with a basic structure containing chains of sodium, water and hydroxide octahedra. The chains are linked together by calcium, water, hydroxide and oxygen polyhedra and massive boron units. The boron units have a formula of 5O6(OH)6sup>3– and a charge of −3. They are composed of three borate tetrahedra and two borate triangular groups. Ulexite is found in evaporite deposits and the precipitated ulexite commonly forms a "cotton ball" tuft of acicular crystals. Ulexite is frequently found associated with colemanite, borax, meyerhofferite, hydro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromate Minerals
Chromate or chromat, and their derived terms, may refer to: Chemistry * Chromate and dichromate, ions * Monochromate, an ion *Trichromate, an ion * Tetrachromate, an ion * Chromate conversion coating, a method for passivating metals Biology *Monochromacy (monochromate) having one color vision *Dichromatism (dichromate) having two color vision *Trichromacy (trichromate) having three color vision * Trichrome staining, a staining method *Tetrachromacy (tetrachromate) having four color vision Other *Chromat, a fashion label *Monochromatic or monochrome, images composed of one color (or values of one color) See also *Chromite, a chromium-containing mineral * Chromite (compound), chemical compounds containing the (CrO2)− anion *Chrome (other) Chrome may refer to: Materials * Chrome plating, a process of surfacing with chromium * Chrome alum, a chemical used in mordanting and photographic film Computing * Google Chrome, a web browser developed by Google ** Chr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Potassium Minerals
Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmospheric oxygen to form flaky white potassium peroxide in only seconds of exposure. It was first isolated from potash, the ashes of plants, from which its name derives. In the periodic table, potassium is one of the alkali metals, all of which have a single valence electron in the outer electron shell, that is easily removed to create an ion with a positive charge – a cation, that combines with anions to form salts. Potassium in nature occurs only in ionic salts. Elemental potassium reacts vigorously with water, generating sufficient heat to ignite hydrogen emitted in the reaction, and burning with a lilac- colored flame. It is found dissolved in sea water (which is 0.04% potassium by weight), and occurs in many minerals such as orthoclase, a c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
James Dwight Dana
James Dwight Dana Royal Society of London, FRS FRSE (February 12, 1813 – April 14, 1895) was an American geologist, mineralogist, volcanologist, and zoologist. He made pioneering studies of mountain-building, volcano, volcanic activity, and the origin and structure of continents and oceans around the world. His zoological author abbreviation is Dana. Early life and career Dana was born February 12, 1813, in Utica, New York. His father was merchant James Dana (1780–1860) and his mother was Harriet Dwight (1792–1870). Through his mother he was related to the Dwight New England family of missionaries and educators including uncle Harrison Gray Otis Dwight and first cousin Henry Otis Dwight. He showed an early interest in science, which had been fostered by Fay Edgerton, a teacher in the Utica high school, and in 1830 he entered Yale College in order to study under Benjamin Silliman the elder. Graduating in 1833, for the next two years he was teacher of mathematics to midshi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclinic Crystal 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 organ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chile
Chile, officially the Republic of Chile, is a country in the western part of South America. It is the southernmost country in the world, and the closest to Antarctica, occupying a long and narrow strip of land between the Andes to the east and the Pacific Ocean to the west. Chile covers an area of , with a population of 17.5 million as of 2017. It shares land borders with Peru to the north, Bolivia to the north-east, Argentina to the east, and the Drake Passage in the far south. Chile also controls the Pacific islands of Juan Fernández, Isla Salas y Gómez, Desventuradas, and Easter Island in Oceania. It also claims about of Antarctica under the Chilean Antarctic Territory. The country's capital and largest city is Santiago, and its national language is Spanish. Spain conquered and colonized the region in the mid-16th century, replacing Inca rule, but failing to conquer the independent Mapuche who inhabited what is now south-central Chile. In 1818, after declaring in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countries of Namibia, Botswana, and Zimbabwe; and to the east and northeast by Mozambique and Eswatini. It also completely enclaves the country Lesotho. It is the southernmost country on the mainland of the Old World, and the second-most populous country located entirely south of the equator, after Tanzania. South Africa is a biodiversity hotspot, with unique biomes, plant and animal life. With over 60 million people, the country is the world's 24th-most populous nation and covers an area of . South Africa has three capital cities, with the executive, judicial and legislative branches of government based in Pretoria, Bloemfontein, and Cape Town respectively. The largest city is Johannesburg. About 80% of the population are Black South Afri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bushveld Igneous Complex
The Bushveld Igneous Complex (BIC) is the largest layered igneous intrusion within the Earth's crust. It has been tilted and eroded forming the outcrops around what appears to be the edge of a great geological basin: the Transvaal Basin. It is approximately 2 billion years old and is divided into four different limbs: the northern, southern, eastern, and western limbs. The Bushveld Complex comprises the Rustenburg Layered suite, the Lebowa Granites and the Rooiberg Felsics, that are overlain by the Karoo sediments. The site was first discovered around 1897 by Gustaaf Molengraaff. Located in South Africa, the BIC contains some of the richest ore deposits on Earth. The complex contains the world's largest reserves of platinum-group metals (PGMs) or platinum group elements (PGEs)—platinum, palladium, osmium, iridium, rhodium, and ruthenium along with vast quantities of iron, tin, chromium, titanium and vanadium. These are used in, but not limited to, jewellery, automobiles and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Atacama
The Atacama Desert ( es, Desierto de Atacama) is a desert plateau in South America covering a 1,600 km (990 mi) strip of land on the Pacific coast, west of the Andes Mountains. The Atacama Desert is the driest nonpolar desert in the world, and the second driest overall, just behind some very specific spots within the McMurdo Dry Valleys as well as the only hot true desert to receive less precipitation than the polar deserts, and the largest fog desert in the world. Both regions have been used as experimentation sites on Earth for Mars expedition simulations. The Atacama Desert occupies , or if the barren lower slopes of the Andes are included. Most of the desert is composed of stony terrain, salt lakes (''salares''), sand, and felsic lava that flows towards the Andes. The desert owes its extreme aridity to a constant temperature inversion due to the cool north-flowing Humboldt ocean current and to the presence of the strong Pacific anticyclone. The most arid regio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triclinic Crystal System
180px, Triclinic (a ≠ b ≠ c and α ≠ β ≠ γ ) In crystallography, the triclinic (or anorthic) crystal system is one of the 7 crystal systems. A crystal system is described by three basis vectors. In the triclinic system, the crystal is described by vectors of unequal length, as in the orthorhombic system. In addition, the angles between these vectors must all be different and may not include 90°. The triclinic lattice is the least symmetric of the 14 three-dimensional Bravais lattices. It has (itself) the minimum symmetry all lattices have: points of inversion at each lattice point and at 7 more points for each lattice point: at the midpoints of the edges and the faces, and at the center points. It is the only lattice type that itself has no mirror planes. Crystal classes The triclinic crystal system class names, examples, Schönflies notation, Hermann-Mauguin notation, point groups, International Tables for Crystallography space group number, orbifold, type, and sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
