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Andyrobertsite
Andyrobertsite is a rare, complex arsenate mineral with a blue color. It is found in the Tsumeb mine in Namibia Namibia, officially the Republic of Namibia, is a country on the west coast of Southern Africa. Its borders include the Atlantic Ocean to the west, Angola and Zambia to the north, Botswana to the east and South Africa to the south; in the no ... and named after Andrew C. Roberts (b. 1950), mineralogist with the Geological Survey of Canada. A Ca-rich analogue (with Ca instead of Cd) is called calcioandyrobertsite and has a more greenish tint. References Arsenate minerals Monoclinic minerals Minerals in space group 11 {{mineral-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsenate Mineral
Arsenate minerals usually refer to the naturally occurring orthoarsenates, possessing the (AsO4)3− anion group and, more rarely, other arsenates with anions like AsO3(OH)2− (also written HAsO42−) (example: pharmacolite Ca(AsO3OH).2H2O) or (very rarely) sO2(OH)2sup>− (example: andyrobertsite). Arsenite minerals are much less common. Both the Dana and the Strunz mineral classifications place the arsenates in with the phosphate minerals. Example arsenate minerals include: *Annabergite Ni3(AsO4)2·8H2O * Austinite CaZn(AsO4)(OH) * Clinoclase Cu3(AsO4)(OH)3 * Conichalcite CaCu(AsO4)(OH) * Cornubite Cu5(AsO4)2(OH)4 * Cornwallite Cu2+5(AsO4)2(OH)2 * Erythrite Co3(AsO4)2·8H2O * Mimetite Pb5(AsO4)3Cl * Olivenite Cu2(AsO4)OH Nickel–Strunz Classification -08- Phosphates IMA-CNMNC proposes a new hierarchical scheme (Mills et al., 2009). This list uses it to modify the Classification of Nickel–Strunz (mindat.org, 10 ed, pending publication). *Abbreviations: **"*" - disc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tsumeb
Tsumeb (; ) is a city of around 35,000 inhabitants and the largest town in the Oshikoto Region, Oshikoto region in northern Namibia. Tsumeb, since its founding in 1905, has been primarily a mining town. The town is the site of a deep mine (the lower workings now closed) whose ore deposits with respect to variety, rarity and aesthetics of minerals have been listed among 100 geological heritage sites around the world by the International Union of Geological Sciences (IUGS). History The town was founded in 1905 by German South-West Africa, German colonial power and celebrated its 100th year of existence in 2005. The name Tsumeb is generally pronounced "SOO-meb". The name is not a derivative of German language, German, Afrikaans language, Afrikaans, or English language, English. It has been suggested that it comes from Khoekhoe language, Nama and means either "Place of the moss" or "Place of the frog". Perhaps this old name had something to do with the huge natural hill of green, o ... [...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 Vector (geometric), vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic system. They form a parallelogram prism (geometry), 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. The length a of the primitive cell below equals \frac \sqrt of the conventional cell above. Crystal class ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Namibia
Namibia, officially the Republic of Namibia, is a country on the west coast of Southern Africa. Its borders include the Atlantic Ocean to the west, Angola and Zambia to the north, Botswana to the east and South Africa to the south; in the northeast, approximating a quadripoint, Zimbabwe lies less than 200 metres (660 feet) away along the Zambezi, Zambezi River near Kazungula, Zambia. Namibia's capital and largest city is Windhoek. Namibia is the driest country in sub-Saharan Africa, and has been inhabited since prehistoric times by the Khoekhoe, Khoi, San people, San, Damara people, Damara and Nama people. Around the 14th century, immigration, immigrating Bantu peoples arrived as part of the Bantu expansion. From 1600 the Ovambo people#History, Ovambo formed kingdoms, such as Ondonga and Oukwanyama. In 1884, the German Empire established rule over most of the territory, forming a colony known as German South West Africa. Between 1904 and 1908, German troops waged a punitive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arsenate Minerals
The arsenate is an ion with the chemical formula . Bonding in arsenate consists of a central arsenic atom, with oxidation state +5, Double bond, double bonded to one oxygen atom and Single bond, single bonded to a further three oxygen atoms. The four oxygen atoms orient around the arsenic atom in a Tetrahedral molecular geometry, tetrahedral geometry. Resonance (chemistry), Resonance disperses the ion's −3 charge across all four oxygen atoms. Arsenate readily reacts with metals to form arsenate metal Arsenic compounds, compounds. Arsenate is a moderate Oxidant, oxidizer and an electron acceptor, with an electrode potential of +0.56 Volt, V for its Reduction potential, reduction to arsenite. Due to arsenic having the same Valence (chemistry), valency and similar Atomic radii of the elements (data page), atomic radius to phosphorus, arsenate shares similar Tetrahedral molecular geometry, geometry and Reactivity (chemistry), reactivity with phosphate. Arsenate can replace phosphate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monoclinic Minerals
In crystallography, the monoclinic crystal system is one of the seven crystal systems. A crystal system is described by three Vector (geometric), vectors. In the monoclinic system, the crystal is described by vectors of unequal lengths, as in the orthorhombic system. They form a parallelogram prism (geometry), 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. The length a of the primitive cell below equals \frac \sqrt of the conventional cell above. Crystal class ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
