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Spinel Twin
Spinel () is the magnesium/aluminium member of the larger spinel group of minerals. It has the formula in the cubic crystal system. Its name comes from the Latin word , a diminutive form of ''spine,'' in reference to its pointed crystals. Properties Spinel crystallizes in the isometric system; common crystal forms are octahedra, usually twinned. It has no true cleavage, but shows an octahedral parting and a conchoidal fracture. Its hardness is 8, its specific gravity is 3.5–4.1, and it is transparent to opaque with a vitreous to dull luster. It may be colorless, but is usually various shades of red, lavender, blue, green, brown, black, or yellow. Chromium(III) causes the red color in spinel from Burma. Some spinels are among the most famous gemstones; among them are the Black Prince's Ruby and the "Timur ruby" in the British Crown Jewels, and the "Côte de Bretagne", formerly from the French Crown jewels. The Samarian Spinel is the largest known spinel in the world, weighi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxide Minerals
The oxide mineral class includes those minerals in which the oxide anion (O2−) is bonded to one or more metal alloys. The hydroxide-bearing minerals are typically included in the oxide class. Minerals with complex anion groups such as the Silicate mineral, silicates, Sulfate mineral, sulfates, carbonate mineral, carbonates and Phosphate mineral, phosphates are classed separately. Simple oxides *XO form **Periclase group ***Periclase ***Manganosite **Zincite group ***Zincite ***Bromellite ***Tenorite ***Litharge * form **Cuprite **Ice * form **Hematite group ***Corundum ***Hematite ***Ilmenite * form **Rutile group ***Rutile ***Pyrolusite ***Cassiterite **Baddeleyite **Uraninite **Thorianite * form **Spinel group ***Spinel ***Gahnite ***Magnetite ***Franklinite ***Chromite **Chrysoberyl **Columbite *Hydroxide subgroup: **Brucite **Manganite **Romanèchite **Goethite group: ***Diaspore ***Goethite Nickel–Strunz class 4: oxides Internationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Gravity
Relative density, also called specific gravity, is a dimensionless quantity defined as the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for solids and liquids is nearly always measured with respect to water at its densest (at ); for gases, the reference is air at room temperature (). The term "relative density" (abbreviated r.d. or RD) is preferred in SI, whereas the term "specific gravity" is gradually being abandoned. If a substance's relative density is less than 1 then it is less dense than the reference; if greater than 1 then it is denser than the reference. If the relative density is exactly 1 then the densities are equal; that is, equal volumes of the two substances have the same mass. If the reference material is water, then a substance with a relative density (or specific gravity) less than 1 will float in water. For example, an ice cube, with a relative density of about 0.91, will float. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gorno Badakhshan
Gorno-Badakhshan, officially the Badakhshan Mountainous Autonomous Region, is an autonomous region in eastern Tajikistan, in the Pamir Mountains. It makes up nearly forty-five percent of the country's land area but only two percent of its population.''Population of the Republic of Tajikistan as of 1 January 2008'', State Statistical Committee, Dushanbe, 2008 Name The official English name of the autonomous region is the Badakhshan Mountainous Autonomous Region. The name ''Badakhshan'' (from ; ) is derived from the Sasanian title or . "Gorno-Badakhshan" literally means "mountainous Badakhshan" and is derived from the Russian name of the autonomous region, (literally Gorno-Badakshan autonomous ''oblast''). The Russian abbreviation "GBAO" is also commonly used in English-language publications by national and international bodies such as the government of Tajikistan and the United Nations. History Borders and political authority in the Western Pamir had always been contest ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sanskrit
Sanskrit (; stem form ; nominal singular , ,) is a classical language belonging to the Indo-Aryan languages, Indo-Aryan branch of the Indo-European languages. It arose in northwest South Asia after its predecessor languages had Trans-cultural diffusion, diffused there from the northwest in the late Bronze Age#South Asia, Bronze Age. Sanskrit is the sacred language of Hinduism, the language of classical Hindu philosophy, and of historical texts of Buddhism and Jainism. It was a lingua franca, link language in ancient and medieval South Asia, and upon transmission of Hindu and Buddhist culture to Southeast Asia, East Asia and Central Asia in the early medieval era, it became a language of religion and high culture, and of the political elites in some of these regions. As a result, Sanskrit had a lasting effect on the languages of South Asia, Southeast Asia and East Asia, especially in their formal and learned vocabularies. Sanskrit generally connotes several Indo-Aryan languages# ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxus River
The Amu Darya ( ),() also shortened to Amu and historically known as the Oxus ( ), is a major river in Central Asia, which flows through Tajikistan, Turkmenistan, Uzbekistan, and Afghanistan. Rising in the Pamir Mountains, north of the Hindu Kush, the Amu Darya is formed by the confluence of the Vakhsh and Panj rivers, in the Tigrovaya Balka Nature Reserve on the border between Afghanistan and Tajikistan, and flows from there north-westwards into the southern remnants of the Aral Sea. In its upper course, the river forms part of Afghanistan's northern border with Tajikistan, Uzbekistan, and Turkmenistan. In ancient history, the river was regarded as the boundary of Greater Iran with Turan, which roughly corresponded to present-day Central Asia.B. SpulerĀmū Daryā in Encyclopædia Iranica, online ed., 2009 The Amu Darya has a flow of about 70 cubic kilometres per year on average. Names In classical antiquity, the river was known as the in Latin and () in Greek — a clea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Panj River
The Panj ( , ), traditionally known as the Ochus River, is a river in Afghanistan and Tajikistan and a tributary of the Amu Darya. The river is long and has a basin area of .Пяндж (река) It forms a considerable part of the Afghanistan–Tajikistan border. The river is formed by the confluence of the Pamir River and the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asia
Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which has long been home to the majority of the human population, was the site of many of the first civilisations. Its 4.7 billion people constitute roughly 60% of the world's population. Asia shares the landmass of Eurasia with Europe, and of Afro-Eurasia with both Europe and Africa. In general terms, it is bounded on the east by the Pacific Ocean, on the south by the Indian Ocean, and on the north by the Arctic Ocean. The border of Asia with Europe is a social constructionism, historical and cultural construct, as there is no clear physical and geographical separation between them. A commonly accepted division places Asia to the east of the Suez Canal separating it from Africa; and to the east of the Turkish straits, the Ural Mountains an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Badakhshan
Badakhshan is a historical region comprising the Wakhan Corridor in northeast Afghanistan, eastern Tajikistan, and Taxkorgan Tajik Autonomous County in China. Badakhshan Province is one of the 34 provinces of Afghanistan. Much of historic Badakhshan lies within Tajikistan's Gorno-Badakhshan Autonomous Region in the southeastern part of the country. The music of Badakhshan is an important part of the region's cultural heritage. Name The name "Badakhshan" (, ''Badaxšân''; ; , ''Badakhshon''; ) is derived from the Sasanian official title ''bēdaxš'' or ''badaxš'', which may be from an earlier *pati-axša; the suffix -''ān'' indicates that the country belonged, or had been assigned as a fief, to a person holding the rank of a '' badaxš''. People Badakhshan has a diverse ethnolinguistic and religious community of Badakhshanites. Tajiks and Pamiris are in the majority while a tiny minority of Kyrgyzs, Uzbeks, Hazaras, and Pashtuns are also found in some villages. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corundum
Corundum is a crystalline form of aluminium oxide () typically containing traces of iron, titanium, vanadium, and chromium. It is a rock (geology), rock-forming mineral. It is a naturally transparency and translucency, transparent material, but can have different colors depending on the presence of transition metal impurities in its crystalline structure. Corundum has two primary gemstone, gem varieties: ruby and sapphire. Rubies are red due to the presence of chromium, and sapphires exhibit a range of colors depending on what transition metal is present. A rare type of sapphire, Sapphire#Padparadscha, padparadscha sapphire, is pink-orange. The name "corundum" is derived from the Tamil language, Tamil-Dravidian languages, Dravidian word ''kurundam'' (ruby-sapphire) (appearing in Sanskrit as ''kuruvinda''). Because of corundum's hardness (pure corundum is defined to have 9.0 on the Mohs scale), it can scratch almost all other minerals. Emery (rock), Emery, a variety of corundum w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crown Jewels Of The United Kingdom
The Crown Jewels of the United Kingdom, originally the Crown Jewels of England, are a collection of royal ceremonial objects kept in the Jewel House at the Tower of London, which include the coronation regalia and vestments worn by British monarchs. The coronation regalia are the only working set in Europe and the collection is the most historically complete of any royal regalia in the world. Objects used at the coronation ceremony variously denote the monarch's roles as head of state of the United Kingdom, Supreme Governor of the Church of England, and head of the British armed forces. The regalia feature heraldic devices and national emblems of England, Scotland, Wales, Northern Ireland, and other Commonwealth countries. Use of regalia by monarchs in England can be traced back to when the country was converted to Christianity in the Early Middle Ages. A permanent set of coronation regalia, once belonging to Edward the Confessor, was established after he was made a saint in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Timur Ruby
The Timur Ruby (also ''Khiraj-i-alam'', "Tribute to the World") is an unfaceted, polished red spinel set in a necklace. It is named after the ruler Timur,Morgan, Diane (2008). ''Fire and Blood: Rubies in Myth, Magic, and History.'' Greenwood Publishing Group, founder of the Timurid Empire and purportedly one of its former owners. It was believed to be a ruby until 1851. It is inscribed with the titles of five of its previous owners: Jahangir (who also had the name of his father Akbar the Great inscribed), Shah Jahan, Farrukhsiyar, Nader Shah and Ahmad Shah Durrani.Ball V. (1894)A Description of Two Large Spinel Rubies, with Persian Characters Engraved upon Them.'' Proceedings of the Royal Irish Academy'' Vol. 3, (1893–1896), pp. 380–400 Since 1612, the owners of the Timur ruby have also owned the Koh-i-Noor diamond. It has been in the possessions of the Safavid, Mughal, Sikh and British empires, and is currently part of the Royal Collection. History Origins Spinels ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
