HOME
*



picture info

Billon (alloy)
Billon () is an alloy of a precious metal (most commonly silver, but also gold) with a majority base metal content (such as copper). It is used chiefly for making coins, medals, and token coins. The word comes from the French ''bille'', which means "log". History The use of billon coins dates from ancient Greece and continued through the Middle Ages. During the sixth and fifth centuries BC, some cities on Lesbos used coins made of 60% copper and 40% silver. In both ancient times and the Middle Ages, leaner mixtures were adopted, with less than 2% silver content. Billon coins are perhaps best known from the Roman Empire, where progressive debasements of the Roman ''denarius'' and the Roman provincial '' tetradrachm'' in the second century AD led to declining silver and increasing bronze content in these denominations of coins. Eventually, by the third quarter of the second century AD, these coins were almost entirely bronze, with only a thin coating or even a wash of si ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Dirham Almotadid 20320
The dirham, dirhem or dirhm ( ar, درهم) is a silver unit of currency historically and currently used by several Arab and Arab influenced states. The term has also been used as a related unit of mass. Unit of mass The dirham was a unit of weight used across North Africa, the Middle East, Persia and Ifat; later known as Adal, with varying values. The value of Islamic dirham was 14 qirat, 10 dirham = 7 mithqal, in Islamic law (2.975 gm of silver). In the late Ottoman Empire ( ota, درهم), the standard dirham was 3.207 g; 400 dirhem equal one oka. The Ottoman dirham was based on the Sasanian drachm (in Middle Persian: ''drahm''), which was itself based on the Roman dram/drachm. In Egypt in 1895, it was equivalent to 47.661 troy grains (3.088 g). There is currently a movement within the Islamic world to revive the dirham as a unit of mass for measuring silver, although the exact value is disputed (either 3 or 2.975 grams). History The word "dirham" ultimately ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Denarius
The denarius (, dēnāriī ) was the standard Roman silver coin from its introduction in the Second Punic War to the reign of Gordian III (AD 238–244), when it was gradually replaced by the antoninianus. It continued to be minted in very small quantities, likely for ceremonial purposes, until and through the Tetrarchy (293–313). The word ''dēnārius'' is derived from the Latin ''dēnī'' "containing ten", as its value was originally of 10 assēs.Its value was increased to 16 assēs in the middle of the 2nd century BC. The word for "money" descends from it in Italian (''denaro''), Slovene (''denar''), Portuguese (''dinheiro''), and Spanish (''dinero''). Its name also survives in the dinar currency. Its symbol is represented in Unicode as 𐆖 (U+10196), a numeral monogram that appeared on the obverse in the Republican period, denoting the 10 asses ("X") to 1 denarius ("I") conversion rate. However it can also be represented as X̶ (capital letter X with combining l ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Currency Production
A currency, "in circulation", from la, currens, -entis, literally meaning "running" or "traversing" is a standardization of money in any form, in use or circulation as a medium of exchange, for example banknotes and coins. A more general definition is that a currency is a ''system of money'' in common use within a specific environment over time, especially for people in a nation state. Under this definition, the British Pound Sterling (£), euros (€), Japanese yen (¥), and U.S. dollars (US$)) are examples of (government-issued) fiat currencies. Currencies may act as stores of value and be traded between nations in foreign exchange markets, which determine the relative values of the different currencies. Currencies in this sense are either chosen by users or decreed by governments, and each type has limited boundaries of acceptance - i.e. legal tender laws may require a particular unit of account for payments to government agencies. Other definitions of the term "currency ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  




Precious Metal Alloys
Precious may refer to: Music * Precious (group), a British female pop group Albums * ''Precious'' (Chanté Moore album), 1992 * ''Precious'' (Cubic U album), 1998 * ''Precious'' (Ours album), 2002 * ''Precious'' (Precious album), 2000 * ''Precious'' (soundtrack), the soundtrack album to the 2009 film Songs * "Precious" (Depeche Mode song), 2005 * "Precious" (The Jam song), 1982 * "Precious" (Annie Lennox song), 1992 * "Precious" (Pretenders song), 1980 * "Precious" (Vivid song), 2010 * "Precious" (Yuna Ito song), 2006 * "Precious", a song by Jim Jones on the album '' Pray IV Reign'' * "Precious...", a song by Luna Sea on the album ''Luna Sea'' * "Precious", a song by Minipop on the album ''A New Hope'' * "Precious", a 2010 song by Ace of Base Film and television * ''Precious'' (film), a 2009 American drama film * Precious (Passions character), an orangutan in the soap opera ''Passions'' * Precious (Boukenger), fictional artifacts in the Japanese tokusatsu se ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Coin
A coin is a small, flat (usually depending on the country or value), round piece of metal or plastic used primarily as a medium of exchange or legal tender. They are standardized in weight, and produced in large quantities at a mint in order to facilitate trade. They are most often issued by a government A government is the system or group of people governing an organized community, generally a state. In the case of its broad associative definition, government normally consists of legislature, executive, and judiciary. Government i .... Coins often have images, numerals, or text on them. Obverse and reverse, ''Obverse'' and its opposite, ''reverse'', refer to the two flat faces of coins and medals. In this usage, ''obverse'' means the wikt:front, front face of the object and ''reverse'' means the wikt:back, back face. The obverse of a coin is commonly called ''heads'', because it often depicts the head of a prominent person, and the reverse ''tails''. Coins a ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Shakudō
''Shakudō'' (赤銅) is a Japanese billon of gold and copper (typically 4–10% gold, 96–90% copper), one of the '' irogane'' class of colored metals, which can be treated to develop a black, or sometimes indigo, patina, resembling lacquer. Unpatinated ''shakudō'' visually resembles bronze; the dark color is induced by the '' niiro'' artificial patination process, involving boiling in a solution, generally including ''rokushō''. Naming The characters in the name ''shaku-dō'' mean "red" and "copper" but combined they represent this material which begins with a darkened coppery-bronze color and is then modified to black or near-black. History Early uses The word "shakudō" first appears in records of the Japanese "Nara" period (710-784 AD), but it is not clear to what it referred (it could have been some form of copper, or a form of the now-known material). There are actual pieces known from the 12th century onwards. Shakudō was historically used to construct or decorate ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Antoninianus
The ''antoninianus'' or pre-reform radiate, was a coin used during the Roman Empire thought to have been valued at 2 denarii. It was initially silver, but was slowly debased to bronze with a minimal silver content. The coin was introduced by Caracalla in early 215 AD. It was silver, similar to the denarius except that it was slightly larger and featured the emperor wearing a radiate crown, indicating it was a double denomination. Antoniniani depicting women (usually the emperor's wife) featured the bust resting upon a crescent moon. Even at its introduction, the silver content of the antoninianus was only equal to 1.5 denarii. This created inflation: people rapidly hoarded the denarii (Gresham's law), while both buyers and sellers recognized the new coin had a lower intrinsic value and elevated their prices to compensate. Silver bullion supplies began running short because the Roman Empire was no longer conquering new territory, the Iberian silver mines had been ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


List Of Alloys
This is a list of named alloys grouped alphabetically by base metal. Within these headings, the alloys are also grouped alphabetically. Some of the main alloying elements are optionally listed after the alloy names. Alloys by base metal Aluminium * AA-8000: used for electrical building wire in the U.S. per the National Electrical Code, replacing AA-1350. * Al–Li (2.45% lithium): aerospace applications, including the Space Shuttle * Alnico (nickel, cobalt): used for permanent magnets * Aluminium–Scandium (scandium) * Birmabright (magnesium, manganese): used in car bodies, mainly used by Land Rover cars. * Duralumin (copper) * Hiduminium or R.R. alloys (2% copper, iron, nickel): used in aircraft pistons * Hydronalium (up to 12% magnesium, 1% manganese): used in shipbuilding, resists seawater corrosion * Italma (3.5% magnesium, 0.3% manganese): formerly used to make coinage of the Italian lira * Magnalium (5-50% magnesium): used in airplane bodies, ladders, pyrotechnics ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Bullion
Bullion is non-ferrous metal that has been refined to a high standard of elemental purity. The term is ordinarily applied to bulk metal used in the production of coins and especially to precious metals such as gold and silver. It comes from the Anglo-Norman term for a melting-house where metal was refined, and earlier from French , "boiling". Although precious metal bullion is no longer used to make coins for general circulation, it continues to be held as an investment with a reputation for stability in periods of economic uncertainty. To assess the purity of gold bullion, the centuries-old technique of fire assay is still employed, together with modern spectroscopic instrumentation, to accurately determine its quality. As investment The specifications of bullion are often regulated by market bodies or legislation. In the European Union, the minimum purity for gold to be referred to as "bullion", which is treated as investment gold with regard to taxation, is 99.5% for ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Metal
A metal (from ancient Greek, Greek μέταλλον ''métallon'', "mine, quarry, metal") is a material that, when freshly prepared, polished, or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. Metals are typically ductile (can be drawn into wires) and malleable (they can be hammered into thin sheets). These properties are the result of the ''metallic bond'' between the atoms or molecules of the metal. A metal may be a chemical element such as iron; an alloy such as stainless steel; or a molecular compound such as polythiazyl, polymeric sulfur nitride. In physics, a metal is generally regarded as any substance capable of conducting electricity at a temperature of absolute zero. Many elements and compounds that are not normally classified as metals become metallic under high pressures. For example, the nonmetal iodine gradually becomes a metal at a pressure of between 40 ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Monticello
Monticello ( ) was the primary plantation of Founding Father Thomas Jefferson, the third president of the United States, who began designing Monticello after inheriting land from his father at age 26. Located just outside Charlottesville, Virginia, in the Piedmont region, the plantation was originally , with Jefferson using the labor of enslaved Africans for extensive cultivation of tobacco and mixed crops, later shifting from tobacco cultivation to wheat in response to changing markets. Due to its architectural and historic significance, the property has been designated a National Historic Landmark. In 1987, Monticello and the nearby University of Virginia, also designed by Jefferson, were together designated a UNESCO World Heritage Site. The current nickel, a United States coin, features a depiction of Monticello on its reverse side. Jefferson designed the main house using neoclassical design principles described by Italian Renaissance architect Andrea Palladio and rew ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]  


picture info

Jefferson Nickel
The Jefferson nickel has been the five-cent coin struck by the United States Mint since 1938, when it replaced the Buffalo nickel. From 1938 until 2004, the copper-nickel coin's obverse featured a profile depiction of founding father and third U.S. President Thomas Jefferson by artist Felix Schlag; the obverse design used in 2005 was also in profile, though by Joe Fitzgerald. Since 2006 Jefferson's portrayal, newly designed by Jamie Franki, faces forward. The coin's reverse is still the Schlag original, although in 2004 and 2005 the piece bore commemorative designs. First struck in 1913, the Buffalo nickel had long been difficult to coin, and after it completed the 25-year term during which it could be replaced only by Congress, the Mint moved quickly to replace it with a new design. The Mint conducted a design competition, in early 1938, requiring that Jefferson be depicted on the obverse and Jefferson's house Monticello on the reverse. Schlag won the competition, but wa ...
[...More Info...]      
[...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]