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Alamosite
Alamosite ( Pb12 Si12 O36) is a colorless silicate mineral named after the place where it was discovered, Álamos, Sonora, Mexico. It is a rare secondary mineral occurring in the oxidized zones of lead-rich deposits. For example, the infobox picture shows its association with black leadhillite Leadhillite is a lead sulfate carbonate hydroxide mineral, often associated with anglesite. It has the formula Pb4SO4(CO3)2(OH)2. Leadhillite crystallises in the monoclinic system, but develops pseudo-hexagonal forms due to crystal twinning. It .... References Inosilicates Monoclinic minerals Minerals in space group 13 {{silicate-mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inosilicates
Silicate minerals are rock-forming minerals made up of silicate groups. They are the largest and most important class of minerals and make up approximately 90 percent of Earth's crust. In mineralogy, silica (silicon dioxide, ) is usually considered a silicate mineral. Silica is found in nature as the mineral quartz, and its polymorphs. On Earth, a wide variety of silicate minerals occur in an even wider range of combinations as a result of the processes that have been forming and re-working the crust for billions of years. These processes include partial melting, crystallization, fractionation, metamorphism, weathering, and diagenesis. Living organisms also contribute to this geologic cycle. For example, a type of plankton known as diatoms construct their exoskeletons ("frustules") from silica extracted from seawater. The frustules of dead diatoms are a major constituent of deep ocean sediment, and of diatomaceous earth. General structure A silicate mineral is generally a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leadhillite
Leadhillite is a lead sulfate carbonate hydroxide mineral, often associated with anglesite. It has the formula Pb4SO4(CO3)2(OH)2. Leadhillite crystallises in the monoclinic system, but develops pseudo-hexagonal forms due to crystal twinning. It forms transparent to translucent variably coloured crystals with an adamantine lustre. It is quite soft with a Mohs hardness of 2.5 and a relatively high specific gravity of 6.26 to 6.55. It was discovered in 1832 in the Susannah Mine, Leadhills in the county of Lanarkshire, Scotland. It is trimorphous with susannite and macphersonite (these three minerals have the same formula, but different structures). Leadhillite is monoclinic, susannite is trigonal and macphersonite is orthorhombic. Leadhillite was named in 1832 after the locality. Unit cell Leadhillite belongs to the monoclinic crystal class 2/m, which is the class with the highest symmetry in the monoclinic system. It has a two-fold axis of symmetry perpendicular to a m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lead
Lead is a chemical element with the symbol Pb (from the Latin ) and atomic number 82. It is a heavy metal that is denser than most common materials. Lead is soft and malleable, and also has a relatively low melting point. When freshly cut, lead is a shiny gray with a hint of blue. It tarnishes to a dull gray color when exposed to air. Lead has the highest atomic number of any stable element and three of its isotopes are endpoints of major nuclear decay chains of heavier elements. Lead is toxic, even in small amounts, especially to children. Lead is a relatively unreactive post-transition metal. Its weak metallic character is illustrated by its amphoteric nature; lead and lead oxides react with acids and bases, and it tends to form covalent bonds. Compounds of lead are usually found in the +2 oxidation state rather than the +4 state common with lighter members of the carbon group. Exceptions are mostly limited to organolead compounds. Like the lighter members of the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicon
Silicon is a chemical element with the symbol Si and atomic number 14. It is a hard, brittle crystalline solid with a blue-grey metallic luster, and is a tetravalent metalloid and semiconductor. It is a member of group 14 in the periodic table: carbon is above it; and germanium, tin, lead, and flerovium are below it. It is relatively unreactive. Because of its high chemical affinity for oxygen, it was not until 1823 that Jöns Jakob Berzelius was first able to prepare it and characterize it in pure form. Its oxides form a family of anions known as silicates. Its melting and boiling points of 1414 °C and 3265 °C, respectively, are the second highest among all the metalloids and nonmetals, being surpassed only by boron. Silicon is the eighth most common element in the universe by mass, but very rarely occurs as the pure element in the Earth's crust. It is widely distributed in space in cosmic dusts, planetoids, and planets as various forms of silicon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula . Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins, nucleic acids, carbohydrates, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 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 org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicate Mineral
Silicate minerals are rock-forming minerals made up of silicate groups. They are the largest and most important class of minerals and make up approximately 90 percent of Earth's crust. In mineralogy, silica (silicon dioxide, ) is usually considered a silicate mineral. Silica is found in nature as the mineral quartz, and its polymorphs. On Earth, a wide variety of silicate minerals occur in an even wider range of combinations as a result of the processes that have been forming and re-working the crust for billions of years. These processes include partial melting, crystallization, fractionation, metamorphism, weathering, and diagenesis. Living organisms also contribute to this geologic cycle. For example, a type of plankton known as diatoms construct their exoskeletons ("frustules") from silica extracted from seawater. The frustules of dead diatoms are a major constituent of deep ocean sediment, and of diatomaceous earth. General structure A silicate mineral is generally a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Álamos
Álamos () is a town in Álamos Municipality in the Mexican state of Sonora, in northwestern Mexico. Historically an important center of silver mining, the town's economy is now dominated by the tourist sector. Designated a ''pueblo mágico'' due to its architecture, the town is host to several arts festivals, most notably the Festival Cultural "Alfonso Ortíz Tirado". It also hosts the Alamos Alliance, a yearly summit of economic policy makers, academics and business leaders founded and led by Arnold Harberger that has led to the town being called the "Little Mexican Davos". Name The Municipality of Álamos derives its name from the ( poplar or cottonwood) tree. Several impressive specimens are found in one of its two principal plazas, the Alameda. The nearby hamlet, El Sabinito, located within the municipality, also derives its name from a tree, the (" Montezuma cypress"). History The area was named by the conquistador Francisco Vásquez de Coronado. His expedition of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sonora
Sonora (), officially Estado Libre y Soberano de Sonora ( en, Free and Sovereign State of Sonora), is one of the 31 states which, along with Mexico City, comprise the Federal Entities of Mexico. The state is divided into 72 municipalities; the capital (and largest) city of which being Hermosillo, located in the center of the state. Other large cities include Ciudad Obregón, Nogales (on the Mexico-United States border), San Luis Río Colorado, and Navojoa. Sonora is bordered by the states of Chihuahua to the east, Baja California to the northwest and Sinaloa to the south. To the north, it shares the U.S.–Mexico border primarily with the state of Arizona with a small length with New Mexico, and on the west has a significant share of the coastline of the Gulf of California. Sonora's natural geography is divided into three parts: the Sierra Madre Occidental in the east of the state; plains and rolling hills in the center; and the coast on the Gulf of California. It is pri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatemala, Belize, and the Caribbean Sea; and to the east by the Gulf of Mexico. Mexico covers ,Mexico ''''. . making it the world's 13th-largest country by are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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