|
Ametrine
Ametrine, also known as trystine, golden amethyst, or by the trade name bolivianite, is a variety of quartz with alternating zones of purple and yellow-orange coloration. Its name is a portmanteau of amethyst and citrine. While ametrine is commonly referred to as a combination of these two quartz varieties, some sources claim this is not accurate. Almost all commercially available ametrine is mined in Bolivia. Color Ametrine, as its name suggests, is commonly believed to be a combination of citrine and amethyst in the same crystal. However, sources do not agree that the yellow-orange quartz component of ametrine may properly be called citrine. Like the purple color of amethyst, the yellow color in ametrine originates from trace amounts of iron in the crystal structure. The difference in coloration is due to the iron existing in different oxidation states. The yellow segments have been oxidized by heat, while the amethyst segments remain unoxidized. Some sources define citrine s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quartz
Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical formula of Silicon dioxide, SiO2. Quartz is, therefore, classified structurally as a Silicate mineral#Tectosilicates, framework silicate mineral and compositionally as an oxide mineral. Quartz is the second most abundant mineral in Earth's continental crust, behind feldspar. Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral. The transformation from α-quartz to β-quartz takes place abruptly at . Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Minerals
This is a list of minerals which have Wikipedia articles. Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various ''species''. Within a mineral species there may be variation in physical properties or minor amounts of impurities that are recognized by mineralogists or wider society as a mineral ''variety''. Mineral variety names are listed after the valid minerals for each letter. For a more complete listing of all mineral names, see List of minerals recognized by the International Mineralogical Association. A :Varieties that are not valid species: *Adamantine spar (variety of corundum) *Agate (variety of chalcedony and quartz) *Alabaster (variety of gypsum) *Alexandrite (variety of chrysoberyl) *Allingite (synonym of amber) *Alum *Amazonite (variety of microcline) *Amethyst (purple variety of quartz) *Ametrine (variety of quartz) *Ammolite (organic; also a gemstone) *Amos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Amethyst
Amethyst is a Violet (color), violet variety of quartz. The name comes from the Koine Greek from - , "not" and (Ancient Greek) / (Modern Greek), "intoxicate", a reference to the belief that the stone protected its owner from Alcohol intoxication, drunkenness. Ancient Greece, Ancient Greeks wore amethyst and carved drinking vessels from it in the belief that it would prevent intoxication. Amethyst, a Gemstone, semiprecious stone, is often used in jewelry. Structure Amethyst is a violet variety of quartz () and owes its violet color to Gemstone irradiation, irradiation, impurities of iron () and in some cases other transition metals, and the presence of other trace elements, which result in complex crystal lattice substitutions. The irradiation causes the iron ions that replace silicon, Si in the lattice to lose an electron and form a color center. Amethyst is a three-dimensional network of tetrahedra where the silicon atoms are in the center and are surrounded by fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Citrine Quartz
Citrine is a transparent, yellow variety of quartz. Its name is derived from the Latin word ''citrus'' (citron tree), by way of the French ''citrin'' or ''citron'' (lemon). Citrine is one of the most popular yellow gemstones. It is sometimes used as a modern, more affordable alternative to the traditional November birthstone, topaz. Not every yellow quartz is considered citrine, and there is disagreement as to when the name "citrine" is appropriately used. However, quartz stained by iron inclusions or coatings is generally not considered citrine. Natural citrine is rare; most commercially available citrine is produced by heating amethyst or smoky quartz. Natural citrine tends to have a pale yellow, often smoky color, while heat-treated amethyst is typically a deeper yellow, orange, red, or even brown ("burnt amethyst"). Color File:Citrine 1 (Russie).jpg, Twinned natural citrine crystals from Russia File:Quartz-60953.jpg, Natural citrine crystal from Brazil File:Citrin cut.jpg, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trigonal
In crystallography, the hexagonal crystal family is one of the six crystal family, 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 hexagonal crystal family#Crystal systems, 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 rhom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smoky Quartz
Smoky quartz is a brownish grey, translucent variety of quartz that ranges in clarity from almost complete transparency to an almost-opaque brownish-gray or black crystals. The color of smoky quartz is produced when natural radiation, emitted from the surrounding rock, activates color centers around aluminum impurities within the crystalline quartz. Varieties Morion is a very dark brown to black opaque variety. Morion is the German, Danish, Spanish and Polish synonym for smoky quartz. The name is from a misreading of ''mormorion'' in Pliny the Elder. Cairngorm is a variety of smoky quartz found in the Cairngorm Mountains of Scotland. It usually has a smoky yellow-brown colour, though some specimens are greyish-brown. It is used in Scottish jewellery and as a decoration on kilt pins and the handles of (anglicised: ''sgian-dubhs'' or ''skean dhu''). The largest known cairngorm crystal is a specimen kept at Braemar Castle. Uses Smoky quartz is common and was not historical ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ayoreo People
The Ayoreo (Ayoreode, Ayoréo, Ayoréode) are an indigenous people of the Gran Chaco. They live in an area surrounded by the Paraguay, Pilcomayo, Parapetí, and Grande Rivers, spanning both Bolivia and Paraguay. There are approximately 5,600 Ayoreo people in total. Around 3,000 live in Bolivia, and 2,600 live in Paraguay. Traditionally nomadic hunter-gatherers, the majority of the population was sedentarized by missionaries in the twentieth century. The few remaining uncontacted Ayoreo are threatened by deforestation and loss of territory. Name and language The Ayoreo people are known by numerous names including Ayoré, Ayoreode, Guarañoca, Koroino, Moro, Morotoco, Poturero, Pyeta Yovai, Samococio, Sirákua, Takrat, Yanaigua and Zapocó. In the Ayoreo language, Ayoreo means “true people,” and Ayoreode means "human beings."Infantas 2012 They speak the Ayoreo language, which is classified under Zamucoan, a small language family of Paraguay and Bolivia. A grammar and di ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dowry
A dowry is a payment such as land, property, money, livestock, or a commercial asset that is paid by the bride's (woman's) family to the groom (man) or his family at the time of marriage. Dowry contrasts with the related concepts of bride price and dower. While bride price or bride service is a payment by the Bridegroom, groom, or his family, to the bride, or her family, dowry is the wealth transferred from the bride, or her family, to the groom, or his family. Similarly, dower is the property settled on the bride herself, by the groom at the time of marriage, and which remains under her ownership and control. Traditionalist dowry is an ancient custom that is mentioned in some of the earliest writings, and its existence may well predate records of it. Dowries continue to be expected and demanded as a condition to accept a marriage proposal in some parts of the world, mainly in parts of Asia. The custom of dowry is most common in strongly patrilineal cultures that expect women t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spain
Spain, or the Kingdom of Spain, is a country in Southern Europe, Southern and Western Europe with territories in North Africa. Featuring the Punta de Tarifa, southernmost point of continental Europe, it is the largest country in Southern Europe and the fourth-most populous European Union member state. Spanning across the majority of the Iberian Peninsula, its territory also includes the Canary Islands, in the Eastern Atlantic Ocean, the Balearic Islands, in the Western Mediterranean Sea, and the Autonomous communities of Spain#Autonomous cities, autonomous cities of Ceuta and Melilla, in mainland Africa. Peninsular Spain is bordered to the north by France, Andorra, and the Bay of Biscay; to the east and south by the Mediterranean Sea and Gibraltar; and to the west by Portugal and the Atlantic Ocean. Spain's capital and List of largest cities in Spain, largest city is Madrid, and other major List of metropolitan areas in Spain, urban areas include Barcelona, Valencia, Seville, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
