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Tanzanite Foundation
Tanzanite is the blue and violet variety of the mineral zoisite (a calcium aluminium hydroxyl sorosilicate), caused by small amounts of vanadium. Tanzanite belongs to the epidote mineral group. Tanzanite is only found in Simanjiro District of Manyara Region in Tanzania, in a very small mining area (approximately long and wide) near the Mererani Hills. Tanzanite is noted for its remarkably strong trichroism, appearing alternately blue, violet and burgundy depending on crystal orientation. Tanzanite can also appear differently when viewed under different lighting conditions. The blues appear more evident when subjected to fluorescent light and the violet hues can be seen readily when viewed under incandescent illumination. In its rough state tanzanite is colored a reddish brown to clear, and it requires heat treatment to remove the brownish "veil" and bring out the blue violet of the stone. The gemstone was given the name 'tanzanite' by Tiffany & Co. after Tanzania, the countr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sorosilicate
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 general ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ediacaran Period
The Ediacaran Period ( ) is a geological period that spans 96 million years from the end of the Cryogenian Period 635 million years ago (Mya), to the beginning of the Cambrian Period 538.8 Mya. It marks the end of the Proterozoic Eon, and the beginning of the Phanerozoic Eon. It is named after the Ediacara Hills of South Australia. The Ediacaran Period's status as an official geological period was ratified in 2004 by the International Union of Geological Sciences (IUGS), making it the first new geological period declared in 120 years. Although the period takes its name from the Ediacara Hills where geologist Reg Sprigg first discovered fossils of the eponymous Ediacaran biota in 1946, the type section is located in the bed of the Enorama Creek within Brachina Gorge in the Flinders Ranges of South Australia, at . The Ediacaran marks the first appearance of widespread multicellular fauna following the end of Snowball Earth glaciation events, the so-called Ediacaran biota, wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harvard University
Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher learning in the United States and one of the most prestigious and highly ranked universities in the world. The university is composed of ten academic faculties plus Harvard Radcliffe Institute. The Faculty of Arts and Sciences offers study in a wide range of undergraduate and graduate academic disciplines, and other faculties offer only graduate degrees, including professional degrees. Harvard has three main campuses: the Cambridge campus centered on Harvard Yard; an adjoining campus immediately across Charles River in the Allston neighborhood of Boston; and the medical campus in Boston's Longwood Medical Area. Harvard's endowment is valued at $50.9 billion, making it the wealthiest academic institution in the world. Endowment inco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gemological Institute Of America
The Gemological Institute of America (GIA) is a nonprofit institute based in Carlsbad, California. It is dedicated to research and education in the field of gemology and the jewelry arts. Founded in 1931, GIA's mission is to protect buyers and sellers of gemstones by setting and maintaining the standards used to evaluate gemstone quality. The institute does so through research, gem identification and diamond grading services and a variety of educational programs. Through its library and subject experts, GIA acts as a resource of gem and jewelry information for the trade, the public and media outlets. In 1953 the GIA developed its International Diamond Grading System and the "four Cs" (cut, clarity, color, and carat weight) as a standard to compare and evaluate the quality of diamonds. Today, the institute is headquartered in Carlsbad, California and operates in 13 countries, with 11 campuses, 9 laboratories and 4 research centers. History The story of the GIA begins in the 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Saks Fifth Avenue
Saks Fifth Avenue (originally Saks & Company; Colloquialism, colloquially Saks) is an American Luxury goods, luxury department store chain headquartered in New York City and founded by Andrew Saks. The original store opened in the F Street and 7th Street shopping districts, F Street shopping district of Washington, D.C. in 1867. Saks expanded into Manhattan with its Herald Square store in 1902 and Saks Fifth Avenue flagship store, flagship store on Fifth Avenue in 1924. The chain was acquired by Tennessee-based Proffitt's, Inc. (renamed Saks, Inc.) in 1998, and Saks, Inc. was acquired by the Canadian-founded Hudson's Bay Company (HBC) in 2013. Subsidiary Saks Off 5th, originally a clearance store for Saks Fifth Avenue, is now a large off-price retailer in its own right managed independently from Saks Fifth Avenue under HBC. History Early history Andrew Saks was born to a German Jewish family, in Baltimore. He worked as a peddler and paper boy before moving to Washington, D ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Kenya
Mount Kenya (Kikuyu: ''Kĩrĩnyaga'', Kamba, ''Ki Nyaa'') is the highest mountain in Kenya and the second-highest in Africa, after Kilimanjaro. The highest peaks of the mountain are Batian (), Nelion () and Point Lenana (). Mount Kenya is located in the former Eastern and Central provinces of Kenya; its peak is now the intersection of Meru, Embu, Laikipia, Kirinyaga, Nyeri and Tharaka Nithi counties, about south of the equator, around north-northeast of the capital Nairobi. Mount Kenya is the source of the name of the Republic of Kenya. Mount Kenya is a volcano created approximately 3 million years after the opening of the East African Rift. Before glaciation, it was high. It was covered by an ice cap for thousands of years. This has resulted in very eroded slopes and numerous valleys radiating from the peak. There are currently 11 small glaciers, which are shrinking rapidly, and may disappear by 2050. The forested slopes are an important source of water for much of Keny ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beryl
Beryl ( ) is a mineral composed of beryllium aluminium silicate with the chemical formula Be3Al2Si6O18. Well-known varieties of beryl include emerald and aquamarine. Naturally occurring, hexagonal crystals of beryl can be up to several meters in size, but terminated crystals are relatively rare. Pure beryl is colorless, but it is frequently tinted by impurities; possible colors are green, blue, yellow, pink, and red (the rarest). It is an ore source of beryllium. Etymology The word ''beryl'' – enm, beril – is borrowed, via fro, beryl and la, beryllus, from Ancient Greek βήρυλλος ''bḗryllos'', which referred to a 'precious blue-green color-of-sea-water stone'; from Prakrit ''veruḷiya'', ''veḷuriya'' 'beryl' (compare the pseudo-Sanskritization वैडूर्य ''vaiḍūrya'' 'cat's eye; jewel; lapis lazuli', traditionally explained as '(brought) from (the city of) Vidūra'), which is ultimately of Dravidian origin, maybe from the name of Belur o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nairobi
Nairobi ( ) is the capital and largest city of Kenya. The name is derived from the Maasai phrase ''Enkare Nairobi'', which translates to "place of cool waters", a reference to the Nairobi River which flows through the city. The city proper had a population of 4,397,073 in the 2019 census, while the metropolitan area has a projected population in 2022 of 10.8 million. The city is commonly referred to as the Green City in the Sun. Nairobi was founded in 1899 by colonial authorities in British East Africa, as a rail depot on the Uganda - Kenya Railway.Roger S. Greenway, Timothy M. Monsma, ''Cities: missions' new frontier'', (Baker Book House: 1989), p.163. The town quickly grew to replace Mombasa as the capital of Kenya in 1907. After independence in 1963, Nairobi became the capital of the Republic of Kenya. During Kenya's colonial period, the city became a centre for the colony's coffee, tea and sisal industry. The city lies in the south central part of Kenya, at an elevation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dumortierite
Dumortierite is a fibrous variably colored aluminium boro-silicate mineral, Al7BO3(SiO4)3O3. Dumortierite crystallizes in the orthorhombic system typically forming fibrous aggregates of slender prismatic crystals. The crystals are vitreous and vary in color from brown, blue, and green to more rare violet and pink. Substitution of iron and other tri-valent elements for aluminium result in the color variations. It has a Mohs hardness of 7 and a specific gravity of 3.3 to 3.4. Crystals show pleochroism from red to blue to violet. ''Dumortierite quartz'' is blue colored quartz containing abundant dumortierite inclusions. Dumortierite was first described in 1881 for an occurrence in Chaponost, in the Rhône-Alps of France and named for the French paleontologist Eugène Dumortier (1803–1873). It typically occurs in high temperature aluminium rich regional metamorphic rocks, those resulting from contact metamorphism and also in boron rich pegmatites. The most extensive investigation on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peridot
Peridot ( /ˈpɛr.ɪˌdɒt, -ˌdoʊ/ ''PERR-ih-dot, -doh''), sometimes called chrysolite, is a deep yellowish-green transparent variety of olivine. Peridot is one of the few gemstones that only occurs in one color. Peridot can be found in mafic and ultramafic rocks occurring in lava and peridotite xenoliths of the mantle. The gem occurs in silica-deficient rocks such as volcanic basalt and pallasitic meteorites. Peridot is one of only two gems observed to be formed not in the Earth’s crust, but in the molten rock of the upper mantle. Gem-quality peridot is rare on Earth's surface due to its susceptibility to weathering during its movement from deep within the mantle to the surface. Peridot has the formula of (Mg, Fe)2SiO4. Peridot is one of the birthstones for the month of August. Etymology The origin of the name ''peridot'' is uncertain. The ''Oxford English Dictionary'' suggests an alteration of Anglo–Norman (classical Latin -), a kind of opal, rather than the Ara ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olivine
The mineral olivine () is a magnesium iron silicate with the chemical formula . It is a type of nesosilicate or orthosilicate. The primary component of the Earth's upper mantle, it is a common mineral in Earth's subsurface, but weathers quickly on the surface. For this reason, olivine has been proposed as a good candidate for accelerated weathering to sequester carbon dioxide from the Earth's oceans and atmosphere, as part of climate change mitigation. Olivine also has many other historical uses, such as the gemstone peridot (or chrysolite), as well as industrial applications like metalworking processes. The ratio of magnesium to iron varies between the two endmembers of the solid solution series: forsterite (Mg-endmember: ) and fayalite (Fe-endmember: ). Compositions of olivine are commonly expressed as molar percentages of forsterite (Fo) and fayalite (Fa) (''e.g.'', Fo70Fa30). Forsterite's melting temperature is unusually high at atmospheric pressure, almost , while ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Goan
Goans ( kok, गोंयकार, Romi Konkani: , pt, Goeses) is the demonym used to describe the people native to Goa, India, who form an ethno-linguistic group resulting from the assimilation of Indo-Aryan, Dravidian, Indo-Portuguese, and Austro-Asiatic ethnic and/or linguistic ancestries. They speak different dialects of Konkani language natively, collectively known as Goan Konkani. "''Goanese"'' is an incorrect term for Goans. Language Goans are multilingual, but mainly speak the Konkani language, a Prakrit based language belonging to the Southern group of Indo-Aryan Languages. Various dialects of Konkani spoken by the Goans which include ''Bardezkari'', ''Saxtti'', ''Pednekari and'' ''Antruz''. The Konkani spoken by the Catholics is notably different from those of the Hindus, since it has a lot of Portuguese influence in its vocabulary. Konkani was suppressed for official documentation use only not for unofficial use under the Portuguese governance, playing a minor pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
