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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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beryllium
Beryllium is a chemical element with the symbol Be and atomic number 4. It is a steel-gray, strong, lightweight and brittle alkaline earth metal. It is a divalent element that occurs naturally only in combination with other elements to form minerals. Notable gemstones high in beryllium include beryl ( aquamarine, emerald) and chrysoberyl. It is a relatively rare element in the universe, usually occurring as a product of the spallation of larger atomic nuclei that have collided with cosmic rays. Within the cores of stars, beryllium is depleted as it is fused into heavier elements. Beryllium constitutes about 0.0004 percent by mass of Earth's crust. The world's annual beryllium production of 220 tons is usually manufactured by extraction from the mineral beryl, a difficult process because beryllium bonds strongly to oxygen. In structural applications, the combination of high flexural rigidity, thermal stability, thermal conductivity and low density (1.85 times that of water) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emerald
Emerald is a gemstone and a variety of the mineral beryl (Be3Al2(SiO3)6) colored green by trace amounts of chromium or sometimes vanadium.Hurlbut, Cornelius S. Jr. and Kammerling, Robert C. (1991) ''Gemology'', John Wiley & Sons, New York, p. 203, . Beryl has a hardness of 7.5–8 on the Mohs scale. Most emeralds are highly included, so their toughness (resistance to breakage) is classified as generally poor. Emerald is a cyclosilicate. Etymology The word "emerald" is derived (via fro, esmeraude and enm, emeraude), from Vulgar Latin: ''esmaralda''/''esmaraldus'', a variant of Latin ''smaragdus'', which was a via grc, σμάραγδος (smáragdos; "green gem") from a Semitic language. According to Webster's Dictionary the term emerald was first used in the 14th century. Properties determining value Emeralds, like all colored gemstones, are graded using four basic parameters–the four ''C''s of connoisseurship: ''color'', ''clarity,'' ''cut'' and ''carat weight''. N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyclosilicate
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silicate Minerals
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 genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morganite
Morganite is an orange or pink gemstone and is also a variety of beryl. Morganite can be mined in countries like Brazil, Afghanistan, Mozambique, Namibia, the United States, and Madagascar. Morganite has grown in popularity since 2010. ''Brides'' and CNN have even listed it as a good alternative to diamond. Name Morganite is named after J. P. Morgan. Morganite is also known as pink beryl, rose beryl, pink emerald, and "cesian (or ''caesian'') beryl". Characteristics The pink color of morganite is attributed to Mn2+ ions. Morganite is pleochroic, when it is view down its c crystallographic axis the color is more pink. In comparison to emerald, morganite lacks inclusions and fractures. Thus making it more durable than emerald. History Pink beryl of fine color and good sizes was first discovered on an island off the coast of Madagascar in 1910. It was also known, with other gemstone minerals, such as tourmaline and kunzite, at Pala, California. In December 1910, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aquamarine (gem)
Aquamarine is a pale-blue to light-green variety of beryl. The color of aquamarine can be changed by heat. Aquamarine has a chemical composition of Be3Al2Si6O18, also containing Fe2+. It has a hardness of 7.5 to 8. Aquamarine contains no or few noticeable inclusions but it can have inclusions like mica, hematite, or salt-water. Aquamarine is a common gemstone. However, there is a rarer deep blue variant called maxixe, but its color can fade due to sunlight. The color of maxixe is caused by NO3. Dark-blue maxixe color can be produced in green, pink or yellow beryl by irradiating it with high-energy radiation (gamma rays, neutrons or even X-rays). Name and etymology The name ''aquamarine'' comes from ''aqua'' (), and ''marine'', deriving from ''marina'' (). The word ''aquamarine'' was first used in the year 1677. The word ''aquamarine'' has been used as a modifier for other minerals like aquamarine tourmaline, aquamarine emerald, aquamarine chrysolite, aquamarine sapphire, o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pegmatite
A pegmatite is an igneous rock showing a very coarse texture, with large interlocking crystals usually greater in size than and sometimes greater than . Most pegmatites are composed of quartz, feldspar, and mica, having a similar silicic composition to granite. However, rarer intermediate composition and mafic pegmatites are known. Many of the world's largest crystals are found within pegmatites. These include crystals of microcline, quartz, mica, spodumene, beryl, and tourmaline. Some individual crystals are over long. Most pegmatites are thought to form from the last fluid fraction of a large crystallizing magma body. This residual fluid is highly enriched in volatiles and trace elements, and its very low viscosity allows molecules to migrate rapidly to join an existing crystal rather than coming together to form new crystals. This allows a few very large crystals to form. While most pegmatites have a simple composition of minerals common in ordinary igneous roc ... [...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 Bravai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vitreous Lustre
Lustre (British English) or luster (American English; see spelling differences) is the way light interacts with the surface of a crystal, rock, or mineral. The word traces its origins back to the Latin ''lux'', meaning "light", and generally implies radiance, gloss, or brilliance. A range of terms are used to describe lustre, such as ''earthy'', ''metallic'', ''greasy'', and ''silky''. Similarly, the term ''vitreous'' (derived from the Latin for glass, ''vitrum'') refers to a glassy lustre. A list of these terms is given below. Lustre varies over a wide continuum, and so there are no rigid boundaries between the different types of lustre. (For this reason, different sources can often describe the same mineral differently. This ambiguity is further complicated by lustre's ability to vary widely within a particular mineral species). The terms are frequently combined to describe intermediate types of lustre (for example, a "vitreous greasy" lustre). Some minerals exhibit unu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dravidian Languages
The Dravidian languages (or sometimes Dravidic) are a family of languages spoken by 250 million people, mainly in southern India, north-east Sri Lanka, and south-west Pakistan. Since the colonial era, there have been small but significant immigrant communities in Mauritius, Myanmar, Singapore, Malaysia, Indonesia, Philippines, United Kingdom, Australia, France, Canada, Germany, South Africa, and the United States. The Dravidian languages are first attested in the 2nd century BCE, as Tamil-Brahmi script, inscribed on the cave walls in the Madurai and Tirunelveli districts of Tamil Nadu. The Dravidian languages with the most speakers are (in descending order of number of speakers) Telugu, Tamil, Kannada and Malayalam, all of which have long literary traditions. Smaller literary languages are Tulu and Kodava. There are also a number of Dravidian-speaking scheduled tribes, such as the Kurukh in Eastern India and Gondi in Central India. Outside of India, Brahui is mo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belur, Karnataka
Belur () is a town and taluk in Hassan district in the state of Karnataka, India. The town is renowned for its Chennakeshava Temple dedicated to Vishnu, one of the finest examples of Hoysala architecture and the largest Hindu temple complex that has survived from pre-14th-century Karnata-Dravida tradition. A historic site inspired by the teachings of Ramanujacharya, it has been a Vaishnava Hindu pilgrimage center since at least the 12th century. It was also the first capital of the Hoysala dynasty, before they built Dwarasamudra (modern Halebid). Belur is also Town Municipal Council and taluka. The Hoysala monuments at Belur and Halebidu have been proposed as UNESCO World Heritage Sites.Permanent Delegation of India to UNESCO (2014)Sacred Ensembles of the Hoysala UNESCO Geography Belur is situated on the banks of Yagachi River in the Hassan district of south Karnataka. It is about northwest of Hassan and about west from the famous Hindu and Jain temples in Halebid. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karnataka
Karnataka (; ISO: , , also known as Karunāḍu) is a state in the southwestern region of India. It was formed on 1 November 1956, with the passage of the States Reorganisation Act. Originally known as Mysore State , it was renamed ''Karnataka'' in 1973. The state corresponds to the Carnatic region. Its capital and largest city is Bengaluru. Karnataka is bordered by the Lakshadweep Sea to the west, Goa to the northwest, Maharashtra to the north, Telangana to the northeast, Andhra Pradesh to the east, Tamil Nadu to the southeast, and Kerala to the southwest. It is the only southern state to have land borders with all of the other four southern Indian sister states. The state covers an area of , or 5.83 percent of the total geographical area of India. It is the sixth-largest Indian state by area. With 61,130,704 inhabitants at the 2011 census, Karnataka is the eighth-largest state by population, comprising 31 districts. Kannada, one of the classical languages of India, is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
