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Mauritanian Ouguiya
The ouguiya ( ar, rtl=yes, 1=أوقية موريتانية, links=, lit=, translit= (); sign: UM; code: MRU), at one time spelled "ougiya", is the currency of Mauritania. Each ouguiya constitutes five khoums (meaning "one fifth"). As such it is one of two circulating currencies, along with the Malagasy ariary, whose division units are not based on a power of ten. The current ouguiya was introduced in 2018, replacing the old ouguiya at a rate of 1 new ouguiya = 10 old ouguiya, which in turn replaced the CFA franc at a rate of 1 old ouguiya = 5 francs. The name ''ouguiya'' () is the Hassaniya Arabic pronunciation of ''uqiyyah'' ), meaning "ounce". First Ouguiya (MRO) Coins In 1973, coins of (1 khoums), 1, 2, 5, 10 and 20 ouguiya were introduced into circulation. This was the only year that the khoums was minted, as the ouguiya was worth five CFA Francs a khoums was the equivalent of the franc (which had no subdivision). The most recent issues were in 2003 (1 ouguiya) and 2004 (oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Khoums
The khoums (singular and plural in English; ar, خمس, "fifth") is the subdivisory unit of the Mauritanian monetary system, the ouguiya. Five khoums make an ouguiya, hence one khoums can be expressed as 0.2 ouguiya. When the ouguiya was adapted in 1973, it replaced the CFA franc as 5 francs to the ouguiya, thus a khoums was equal to the franc. As the franc had no subdivisional unit, all wealths in francs could be converted to ouigiya with no rounding. On the khoums coin (minted in Kremnica Mint, Slovakia), the obverse is in Arabic with the date of the Islamic calendar and the reverse in French in the Gregorian calendar with national arms on each side, identical to all other Mauritanian coins. However, on the Arabic side, instead of a number like on the other coins, the word is used.http://worldcoingallery.com/countries/coine.php?image=img13/119-1&desc=Mauritania km1 1/5 Ouguiya (1973)&query=Mauritania The khoums is one of only two subdivisions of currency that are not in a m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
100 Mauritania Ouguiya Observe
1 (one, unit, unity) is a number representing a single or the only entity. 1 is also a numerical digit and represents a single unit of counting or measurement. For example, a line segment of ''unit length'' is a line segment of length 1. In conventions of sign where zero is considered neither positive nor negative, 1 is the first and smallest positive integer. It is also sometimes considered the first of the infinite sequence of natural numbers, followed by 2, although by other definitions 1 is the second natural number, following 0. The fundamental mathematical property of 1 is to be a multiplicative identity, meaning that any number multiplied by 1 equals the same number. Most if not all properties of 1 can be deduced from this. In advanced mathematics, a multiplicative identity is often denoted 1, even if it is not a number. 1 is by convention not considered a prime number; this was not universally accepted until the mid-20th century. Additionally, 1 is the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Economy Of Mauritania
} The economy of Mauritania is still largely based on agriculture and livestock, even though most of the nomads and many subsistence farmers were forced into the cities by recurring droughts in the 1970s and 1980s. Mauritania has extensive deposits of iron ore, which account for almost 50% of total exports. The decline in world demand for this ore, however, has led to cutbacks in production. With the current rise in metal prices, gold and copper mining companies are opening mines in the interior. The nation's coastal waters are among the richest fishing areas in the world, but overexploitation by foreigners threatens this key source of revenue. The country's first deep water port opened near Nouakchott in 1986. In recent years, drought and economic mismanagement have resulted in a buildup of foreign debt. In March 1999, the government signed an agreement with a joint World Bank-International Monetary Fund mission on a $54 million enhanced structural adjustment facility (ESAF). Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bronze
Bronze is an alloy consisting primarily of copper, commonly with about 12–12.5% tin and often with the addition of other metals (including aluminium, manganese, nickel, or zinc) and sometimes non-metals, such as phosphorus, or metalloids such as arsenic or silicon. These additions produce a range of alloys that may be harder than copper alone, or have other useful properties, such as ultimate tensile strength, strength, ductility, or machinability. The three-age system, archaeological period in which bronze was the hardest metal in widespread use is known as the Bronze Age. The beginning of the Bronze Age in western Eurasia and India is conventionally dated to the mid-4th millennium BCE (~3500 BCE), and to the early 2nd millennium BCE in China; elsewhere it gradually spread across regions. The Bronze Age was followed by the Iron Age starting from about 1300 BCE and reaching most of Eurasia by about 500 BCE, although bronze continued to be much more widely used than it is in mod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brass
Brass is an alloy of copper (Cu) and zinc (Zn), in proportions which can be varied to achieve different mechanical, electrical, and chemical properties. It is a substitutional alloy: atoms of the two constituents may replace each other within the same crystal structure. Brass is similar to bronze, another copper alloy, that uses tin instead of zinc. Both bronze and brass may include small proportions of a range of other elements including arsenic (As), lead (Pb), phosphorus (P), aluminium (Al), manganese (Mn), and silicon (Si). Historically, the distinction between the two alloys has been less consistent and clear, and modern practice in museums and archaeology increasingly avoids both terms for historical objects in favor of the more general "copper alloy". Brass has long been a popular material for decoration due to its bright, gold-like appearance; being used for drawer pulls and doorknobs. It has also been widely used to make utensils because of its low melting ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bi-metallic Coin
Bi-metallic coins are coins consisting of two (''bi-'') metals or alloys, generally arranged with an outer ring around a contrasting center. Common circulating examples include the €1, €2, United Kingdom £1 and £2, Canadian $2, South Africa R5, Turkish 1 lira and 50 kurus, Indian ₹10 and ₹20, IDR 1K, 2 and 5 PLN, 50 CZK, 100 and 200 HUF, 1 and 2 BGN, Hong Kong $10, Argentine $1 and $2, Brazilian R$1, Chilean $100 and $500, Colombian $500 and $1000, and all Mexican coins of $1 or higher denomination. History Bi-metallic coins and medals have been issued for a long time. The Roman Empire issued special-occasion, large medallions with a center of bronze or copper and an outer ring of orichalcum, starting with the reign of Hadrian. Meanwhile, circulating bi-metallic coins are known from the 17th century. English farthings from 1684 through 1693 were made of tin with a central plug of copper for value. The silver-center cent pattern produced by the U ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stainless Steel
Stainless steel is an alloy of iron that is resistant to rusting and corrosion. It contains at least 11% chromium and may contain elements such as carbon, other nonmetals and metals to obtain other desired properties. Stainless steel's corrosion resistance, resistance to corrosion results from the chromium, which forms a Passivation (chemistry), passive film that can protect the material and self-healing material, self-heal in the presence of oxygen. The alloy's properties, such as luster and resistance to corrosion, are useful in many applications. Stainless steel can be rolled into Sheet metal, sheets, plates, bars, wire, and tubing. These can be used in cookware, cutlery, surgical instruments, major appliances, vehicles, construction material in large buildings, industrial equipment (e.g., in paper mills, chemical plants, water treatment), and storage tanks and tankers for chemicals and food products. The biological cleanability of stainless steel is superior to both alumi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel
Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel is a hard and ductile transition metal. Pure nickel is chemically reactive but large pieces are slow to react with air under standard conditions because a passivation layer of nickel oxide forms on the surface that prevents further corrosion. Even so, pure native nickel is found in Earth's crust only in tiny amounts, usually in ultramafic rocks, and in the interiors of larger nickel–iron meteorites that were not exposed to oxygen when outside Earth's atmosphere. Meteoric nickel is found in combination with iron, a reflection of the origin of those elements as major end products of supernova nucleosynthesis. An iron–nickel mixture is thought to compose Earth's outer and inner cores. Use of nickel (as natural meteoric nickel–iron alloy) has been traced as far back as 3500 BCE. Nickel was first isolated and classified as an e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Steel
Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant typically need an additional 11% chromium. Because of its high tensile strength and low cost, steel is used in buildings, infrastructure, tools, ships, trains, cars, machines, electrical appliances, weapons, and rockets. Iron is the base metal of steel. Depending on the temperature, it can take two crystalline forms (allotropic forms): body-centred cubic and face-centred cubic. The interaction of the allotropes of iron with the alloying elements, primarily carbon, gives steel and cast iron their range of unique properties. In pure iron, the crystal structure has relatively little resistance to the iron atoms slipping past one another, and so pure iron is quite ductile, or soft and easily formed. In steel, small amounts of carbon, other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper
Copper is a chemical element with the symbol Cu (from la, cuprum) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orange color. Copper is used as a conductor of heat and electricity, as a building material, and as a constituent of various metal alloys, such as sterling silver used in jewelry, cupronickel used to make marine hardware and coins, and constantan used in strain gauges and thermocouples for temperature measurement. Copper is one of the few metals that can occur in nature in a directly usable metallic form ( native metals). This led to very early human use in several regions, from circa 8000 BC. Thousands of years later, it was the first metal to be smelted from sulfide ores, circa 5000 BC; the first metal to be cast into a shape in a mold, c. 4000 BC; and the first metal to be purposely alloyed with another metal, tin, to create ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Richat Structure
The Richat Structure, also called ''Guelb er Richât'' ( ar, قلب الريشات, Qalb ar-Rīšāt), is a prominent circular geological feature in the Sahara's Adrar Plateau, near Ouadane, west–central Mauritania, Northwest Africa. In the local dialect, ''Richat'' means ''feather'' and it also is known locally in Arabic as ''tagense''. Tagense refers to the circular opening of the leather pouch used to draw water from local wells. It is an eroded geological dome, in diameter, exposing sedimentary rock in layers which appear as concentric rings. Igneous rock is exposed inside and there are spectacular rhyolites and gabbros which have undergone hydrothermal alteration, and a central megabreccia. The structure is also the location of exceptional accumulations of Acheulean archaeological artifacts. It was selected as one of the first 100 geological heritage sites identified by the International Union of Geological Sciences (IUGS) to be of the highest scientific value. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
