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Numismatic Terminology
This glossary of numismatics is a list of definitions of terms and concepts relevant to numismatics and coin collecting, as well as sub-fields and related disciplines, with concise explanations for the beginner or professional. Numismatics (ancient Greek: , meaning "monetary") is the scientific study of money and its history in all its varied forms. While numismatists are often characterized as studying coins, the discipline also includes the study of other types of money, such as banknotes, stock certificates, medals, medallions, and tokens (also referred to as exonumia). Sub-fields and related fields of numismatics include: * Exonumia, the study of coin-like objects such as token coins and medals, and other items used in place of legal currency or for commemoration. * Notaphily, the study of paper money or banknotes. * Philately, the study of postage stamps. * Scripophily, the study and collection of company share certificates and bonds. A B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Numismatics
Numismatics is the study or collection of currency, including coins, tokens, paper money, medals, and related objects. Specialists, known as numismatists, are often characterized as students or collectors of coins, but the discipline also includes the broader study of money and other means of payment used to resolve debts and exchange good (economics), goods. The earliest forms of money used by people are categorised by collectors as "odd and curious", but the use of other goods in barter exchange is excluded, even where used as a circulating currency (e.g., cigarettes or instant noodles in prison). As an example, the Kyrgyz people used horses as the principal currency unit, and gave small change in sheepskin, lambskins; the lambskins may be suitable for numismatic study, but the horses are not. Many objects have been used for centuries, such as Cowry, cowry shells, precious metals, Cocoa beans#History, cocoa beans, Rai stones, large stones, and Gemstone, gems. Etymology Firs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bond (finance)
In finance, a bond is a type of Security (finance), security under which the issuer (debtor) owes the holder (creditor) a debt, and is obliged – depending on the terms – to provide cash flow to the creditor (e.g. repay the principal (i.e. amount borrowed) of the bond at the Maturity (finance), maturity date and interest (called the coupon (bond), coupon) over a specified amount of time.) The timing and the amount of cash flow provided varies, depending on the economic value that is emphasized upon, thus giving rise to different types of bonds. The interest is usually payable at fixed intervals: semiannual, annual, and less often at other periods. Thus, a bond is a form of loan or IOU. Bonds provide the borrower with external funds to finance long-term investments or, in the case of government bonds, to finance current expenditure. Bonds and Share capital, stocks are both Security (finance), securities, but the major difference between the two is that (capital) stockholders h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold
Gold is a chemical element; it has chemical symbol Au (from Latin ) and atomic number 79. In its pure form, it is a brightness, bright, slightly orange-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal, a group 11 element, and one of the noble metals. It is one of the least reactivity (chemistry), reactive chemical elements, being the second-lowest in the reactivity series. It is solid under standard temperature and pressure, standard conditions. Gold often occurs in free elemental (native state (metallurgy), native state), as gold nugget, nuggets or grains, in rock (geology), rocks, vein (geology), veins, and alluvial deposits. It occurs in a solid solution series with the native element silver (as in electrum), naturally alloyed with other metals like copper and palladium, and mineral inclusions such as within pyrite. Less commonly, it occurs in minerals as gold compounds, often with tellurium (gold tellurides). Gold is resistant to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 , 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 third century AD led to declining silver and increasing 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 sometim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Copper
Copper is a chemical element; it has symbol Cu (from Latin ) 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, unalloyed metallic form. This means that copper is a native metal. This led to very early human use in several regions, from . Thousands of years later, it was the first metal to be smelted from sulfide ores, ; the first metal to be cast into a shape in a mold, ; and the first metal to be purposely alloyed with another metal, tin, to create bronze, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nickel
Nickel is a chemical element; it has 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 classifie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Base Metal
A base metal is a common and inexpensive metal, as opposed to a precious metal such as gold or silver. In numismatics, coins often derived their value from the precious metal content; however, base metals have also been used in coins in the past and today. Specific definitions In contrast to noble metals, base metals may be distinguished by oxidizing or corroding relatively easily and reacting variably with diluted hydrochloric acid (HCl) to form hydrogen. Examples include iron, nickel, lead and zinc. Copper is also considered a base metal because it oxidizes relatively easily, although it does not react with HCl. In mining and economics, the term base metals refers to industrial non-ferrous metals excluding precious metals. These include copper, lead, nickel and zinc. The U.S. Customs and Border Protection agency is more inclusive in its definition of commercial base metals. Its list includes—in addition to copper, lead, nickel, and zinc—the following metals: iron and ste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chop Marks On Coins
Chop marks on coins are Chinese characters stamped or embossed onto coins by merchants in order to validate the weight, authenticity and Fineness, silver content of the coin. Depending on particular technique coins said to have been "chopmarked", "countermarked" and "counterstamped". The earliest chopmarks are found on bronze coins of the Wanli Emperor, Wanli era of the Ming Dynasty. These have become known as "Manila Chopmarks" and are believed to have been marked in Manila by Chinese merchants. The marks are usually small and unclear but occasionally full Chinese characters, or small fish symbols, can be found. The character Tian (天), meaning "Heaven" is known from at least one example. The purpose of such chopmarks has been debated, with one theory suggesting it was a way to mark the premium full sized cash coins when compared to the diminutive small picis cash which were minted during the Wanli era. Nevertheless, these Manila Chopmarks have proven to be the earliest chop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Banker's Mark
A banker's mark (or bankers' mark) is a symbol or letter stamped or scratched into many republican and early imperial Roman coin Roman currency for most of Roman history consisted of gold, silver, 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, ...s, whose purpose is unclear. The marks are found on either the obverse or reverse of a coin. Historians and numismatists have speculated that the marks may have been used to assess the purity of a coin's silver, demonstrate that it was not a plated forgery, for accounting or auditing purposes, or to denote that the coin did or did not have the specified weight. There is also debate as to why these marks stopped appearing after very early imperial Roman coinage. References {{Reflist Roman archaeology Numismatic terminology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metallurgical Assay
A metallurgical assay is a compositional analysis of an ore, metal, or alloy, usually performed in order to test for purity or quality. Some assay methods are suitable for raw materials; others are more appropriate for finished goods. Raw precious metals (bullion) are assayed by an assay office. Silver is assayed by titration, gold by cupellation and platinum by inductively coupled plasma optical emission spectrometry (ICP OES). Precious metal items of art or jewelry are frequently hallmarked (depending upon the requirements of the laws of either the place of manufacture or the place of import). Where required to be hallmarked, semi-finished precious metal items of art or jewelry pass through the official testing channels where they are analyzed or assayed for precious metal content. While different nations permit a variety of legally acceptable finenesses, the assayer is actually testing to determine that the fineness of the product conforms with the statement or claim of f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annealing (metallurgy)
In metallurgy and materials science, annealing is a heat treatment that alters the physical and sometimes chemical properties of a material to increase its ductility and reduce its hardness, making it more workable. It involves heating a material above its recrystallization temperature, maintaining a suitable temperature for an appropriate amount of time and then cooling. In annealing, atoms migrate in the crystal lattice and the number of dislocations decreases, leading to a change in ductility and hardness. As the material cools it recrystallizes. For many alloys, including carbon steel, the crystal grain size and phase composition, which ultimately determine the material properties, are dependent on the heating rate and cooling rate. Hot working or cold working after the annealing process alters the metal structure, so further heat treatments may be used to achieve the properties required. With knowledge of the composition and phase diagram, heat treatment can be used t ... [...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 some of which are harder than copper alone or have other useful properties, such as strength, ductility, or machinability. The archaeological period during which bronze was the hardest metal in widespread use is known as the Bronze Age. The beginning of the Bronze Age in western Eurasia 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, which started 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 modern times. Because historica ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
