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Zemannite
Zemannite is a very rare oxide mineral with the chemical formula Mg0.5ZnFe3+[TeO3]3·4.5H2O. It crystallizes in the hexagonal crystal system and forms small Prism (geometry), prismatic brown crystals. Because of the rarity and small crystal size, zemannite has no applications and serves as a collector's item. History and etymology Zemannite was discovered in 1961 in a tellurium deposit near Moctezuma, Sonora, Mexico as an unnamed new mineral. It was not accepted then by the International Mineralogical Association (IMA) due to the uncertainty in its chemical composition. The mineral structure was solved in 1967 by Eckhart Matzat as is specified. Two years later, the mineral was recognized by the IMA under the name zemannite, in honor of the Austrian mineralogist Josef Zemann (born 1923), who had worked extensively on tellurium minerals.E. Matzat, SJ Wiliam''Zemannite, a new tellurite mineral from Moctezuma, Sonora, Mexico'' Canadian Mineralogist Vol. 10, 1969, pp. 139–140. Later ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zemannite Struct
Zemannite is a very rare oxide mineral with the chemical formula Mg0.5ZnFe3+ eO3sub>3·4.5H2O. It crystallizes in the hexagonal crystal system and forms small prismatic brown crystals. Because of the rarity and small crystal size, zemannite has no applications and serves as a collector's item. History and etymology Zemannite was discovered in 1961 in a tellurium deposit near Moctezuma, Sonora, Mexico as an unnamed new mineral. It was not accepted then by the International Mineralogical Association (IMA) due to the uncertainty in its chemical composition. The mineral structure was solved in 1967 by Eckhart Matzat as is specified. Two years later, the mineral was recognized by the IMA under the name zemannite, in honor of the Austrian mineralogist Josef Zemann (born 1923), who had worked extensively on tellurium minerals.E. Matzat, SJ Wiliam''Zemannite, a new tellurite mineral from Moctezuma, Sonora, Mexico'' Canadian Mineralogist Vol. 10, 1969, pp. 139–140. Later investig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Josef Zemann
Josef Zemann (25 May 1923 – 16 October 2022) was an Austrian mineralogist and geologist. Life and work Zemann was born on 25 May 1923 in Vienna. He studied mineralogy at the University of Vienna where he received his PhD for work with Felix Machatschki in 1946. Zemann worked with Martin J. Buerger at the Massachusetts Institute of Technology in 1951 and 1952. He became director of the Institute of Mineralogy and Crystallography of the University of Göttingen. From 1967 until his retirement in 1989 he was head of the Institute of Mineralogy and Crystallography of the University of Vienna. Zemann died on 16 October 2022, at the age of 99. Honours The mineral Zemannite Zemannite is a very rare oxide mineral with the chemical formula Mg0.5ZnFe3+ eO3·4.5H2O. It crystallizes in the hexagonal crystal system and forms small Prism (geometry), prismatic brown crystals. Because of the rarity and small crystal size, z ... Mg0.5ZnFe3+ eO3sub>3 • 4.5 H2O was named ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hexagonal Crystal System
In crystallography, the hexagonal crystal family is one of the six 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 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 rhombohedral. Each lattice system consists of one Bravais l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sylvanite
Sylvanite or silver gold telluride, chemical formula , is the most common telluride of gold. Properties The gold:silver ratio varies from 3:1 to 1:1. It is a metallic mineral with a color that ranges from a steely gray to almost white. It is closely related to calaverite, which is more purely gold telluride with 3% silver. Sylvanite crystallizes in the monoclinic 2/m system. Crystals are rare and it is usually bladed or granular. It is very soft with a hardness of 1.5–2. It has a high relative density of 8–8.2. Sylvanite is photosensitive and can accumulate a dark tarnish if it is exposed to bright light for too long. Occurrence Sylvanite is found in Transylvania, from which its name is partially derived. It is also found and mined in Australia in the East Kalgoorlie district. In Canada it is found in the Kirkland Lake Gold District, Ontario and the Rouyn District, Quebec. In the United States it occurs in California and in Colorado where it was mined as part of the Crippl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Group
In mathematics, physics and chemistry, a space group is the symmetry group of an object in space, usually in three dimensions. The elements of a space group (its symmetry operations) are the rigid transformations of an object that leave it unchanged. In three dimensions, space groups are classified into 219 distinct types, or 230 types if chiral copies are considered distinct. Space groups are discrete cocompact groups of isometries of an oriented Euclidean space in any number of dimensions. In dimensions other than 3, they are sometimes called Bieberbach groups. In crystallography, space groups are also called the crystallographic or Fedorov groups, and represent a description of the symmetry of the crystal. A definitive source regarding 3-dimensional space groups is the ''International Tables for Crystallography'' . History Space groups in 2 dimensions are the 17 wallpaper groups which have been known for several centuries, though the proof that the list was complete was only ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north toward the East China Sea, Philippine Sea, and Taiwan in the south. Japan is a part of the Ring of Fire, and spans Japanese archipelago, an archipelago of List of islands of Japan, 6852 islands covering ; the five main islands are Hokkaido, Honshu (the "mainland"), Shikoku, Kyushu, and Okinawa Island, Okinawa. Tokyo is the Capital of Japan, nation's capital and largest city, followed by Yokohama, Osaka, Nagoya, Sapporo, Fukuoka, Kobe, and Kyoto. Japan is the List of countries and dependencies by population, eleventh most populous country in the world, as well as one of the List of countries and dependencies by population density, most densely populated and Urbanization by country, urbanized. About three-fourths of Geography of Japan, the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shimoda, Shizuoka
270px, Shimoda City Hall is a city and port located in Shizuoka Prefecture, Japan. , the city had an estimated population of 21,402 in 10,787 households, and a population density of 200 persons per km2. The total area of the city is . In the 1850s, Japan was in political crisis over its increasing inability to maintain its national seclusion policy and the issue of what relations, if any, it should have with foreign powers. For a few years, Shimoda was central to this debate. Geography Shimoda is located at the southern tip of the Izu Peninsula about 100 kilometres southwest of Tokyo. Shimoda's location, with the Amagi Mountains to the north, and the warm Kuroshio Current to the south give the city a humid, sub-tropical climate. Surrounding Municipalities *Shizuoka Prefecture **Minamiizu ** Kawazu ** Matsuzaki Demographics Per Japanese census data, the population of Shimoda has been in slow decline over the past 40 years. Climate The city has a climate characterized by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Luxembourg (province Of Belgium)
Luxembourg (french: Luxembourg ; nl, Luxemburg ; german: Luxemburg ; lb, Lëtzebuerg ; wa, Lussimbork), also called Belgian Luxembourg, is the southernmost Provinces of regions in Belgium, province of Wallonia and of Belgium. It borders on the country of Luxembourg to the east, the France, French departments of Ardennes (department), Ardennes, Meuse (department), Meuse and Meurthe-et-Moselle to the south and southwest, and the Wallonia, Walloon provinces of Namur (province), Namur and Liège (province), Liège to the north. Its capital and largest city is Arlon, in the south-east of the province. It has an area of , making it the largest Belgian province. With around 285,000 residents, it is also the least populated province, with a density of , making it a relatively sparsely settled part of a very densely populated region, as well as the lowest density in Belgium. It is significantly larger (71%), but much less populous than the neighbouring Luxembourg, Grand Duchy of Luxem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belgium
Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to the southwest, and the North Sea to the northwest. It covers an area of and has a population of more than 11.5 million, making it the 22nd most densely populated country in the world and the 6th most densely populated country in Europe, with a density of . Belgium is part of an area known as the Low Countries, historically a somewhat larger region than the Benelux group of states, as it also included parts of northern France. The capital and largest city is Brussels; other major cities are Antwerp, Ghent, Charleroi, Liège, Bruges, Namur, and Leuven. Belgium is a sovereign state and a federal constitutional monarchy with a parliamentary system. Its institutional organization is complex and is structured on both regional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Municipality
A municipality is usually a single administrative division having corporate status and powers of self-government or jurisdiction as granted by national and regional laws to which it is subordinate. The term ''municipality'' may also mean the governing body of a given municipality. A municipality is a general-purpose administrative subdivision, as opposed to a special-purpose district. The term is derived from French and Latin . The English word ''municipality'' derives from the Latin social contract (derived from a word meaning "duty holders"), referring to the Latin communities that supplied Rome with troops in exchange for their own incorporation into the Roman state (granting Roman citizenship to the inhabitants) while permitting the communities to retain their own local governments (a limited autonomy). A municipality can be any political jurisdiction, from a sovereign state such as the Principality of Monaco, to a small village such as West Hampton Dunes, New York. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vielsalm
Vielsalm (; wa, Li Viye Såm) is a municipality of Wallonia located in the province of Luxembourg, Belgium. The town is part of the Arrondissement of Bastogne. It is the place of origin of the House of Salm. On 1 January 2018 the municipality had 7,821 inhabitants. The total area is 139.76 km2, giving a population density of 56 inhabitants per km2. Etymology The village, like Salmchâteau, takes its name from the River Salm. The region is also called the Val de Salm, and Salm region. The word "Salm" comes from the Celtic ''salwa'', meaning ''black'' or ''blurred''. Vielsalm means literally "Old Salm" because, at some point, the Lord moved his castle which became the new town centre. A different popular etymology says Salm and Vielsalm are taken from the German ''Salm'', meaning ''salmon''. The arms of the ancient house of Salm and those of the town are based on this interpretation. Geography Vielsalm is located in the Ardennes mountain range and the highest point within ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
