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Fineness
The fineness of a precious metal object (coin, bar, jewelry, etc.) represents the weight of ''fine metal'' therein, in proportion to the total weight which includes alloying base metals and any impurities. Alloy metals are added to increase hardness and durability of coins and jewelry, alter colors, decrease the cost per weight, or avoid the cost of high-purity refinement. For example, copper is added to the precious metal silver to make a more durable alloy for use in coins, housewares and jewelry. Coin silver, which was used for making silver coins in the past, contains 90% silver and 10% copper, by mass. Sterling silver contains 92.5% silver and 7.5% of other metals, usually copper, by mass. Various ways of expressing fineness have been used and two remain in common use: ''millesimal fineness'' expressed in units of parts per 1,000 and '' karats'' or ''carats'' used only for gold. Karats measure the parts per 24, so that 18 karat = = 75% and 24 karat gold is considered 100% g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Karat
The fineness of a precious metal object (coin, bar, jewelry, etc.) represents the weight of ''fine metal'' therein, in proportion to the total weight which includes alloying base metals and any impurities. Alloy metals are added to increase hardness and durability of coins and jewelry, alter colors, decrease the cost per weight, or avoid the cost of high-purity refinement. For example, copper is added to the precious metal silver to make a more durable alloy for use in coins, housewares and jewelry. Coin silver, which was used for making silver coins in the past, contains 90% silver and 10% copper, by mass. Sterling silver contains 92.5% silver and 7.5% of other metals, usually copper, by mass. Various ways of expressing fineness have been used and two remain in common use: ''millesimal fineness'' expressed in units of parts per 1,000 and '' karats'' or ''carats'' used only for gold. Karats measure the parts per 24, so that 18 karat = = 75% and 24 karat gold is considered 100% go ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hallmark
A hallmark is an official mark or series of marks struck on items made of metal, mostly to certify the content of noble metals—such as platinum, gold, silver and in some nations, palladium. In a more general sense, the term '' hallmark'' can also be used to refer to any distinguishing mark. General overview Historically, hallmarks were applied by a trusted party: the "guardians of the craft" or, more recently, by an assay office. Hallmarks are a guarantee of certain purity or fineness of the metal, as determined by official metal (assay) testing. Distinguishment Hallmarks are often confused with "trademarks" or "maker's marks". A hallmark is not the mark of a manufacturer to distinguish their products from other manufacturers' products: that is the function of trademarks or makers' marks. To be a true hallmark, it must be the guarantee of an independent body or authority that the contents are as marked. Thus, a stamp of "925" by itself is not, strictly speaking, a hallmark, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Good Delivery
The Good Delivery specification is a set of rules issued by the London Bullion Market Association (LBMA) describing the physical characteristics of gold and silver bars used in settlement in the wholesale London bullion market. It also puts forth requirements for listing on the LBMA Good Delivery List of approved refineries. Good Delivery bars are notable for their large size and high purity. They are the type normally used in the major international markets (Hong Kong, London, New York, Sydney, Tokyo, and Zürich) and in the gold reserves of governments, central banks, and the IMF. ''The Good Delivery Rules for Gold and Silver Bars'' The entire Good Delivery specification is contained in the LBMA document titled ''The Good Delivery Rules for Gold and Silver Bars: Specifications for Good Delivery Bars and Application Procedures for Listing''. The document includes specific requirements regarding the fineness, weight, dimensions, appearance, marks, and production of gold and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gold
Gold is a chemical element with the symbol Au (from la, aurum) and atomic number 79. This makes it one of the higher atomic number elements that occur naturally. It is a bright, slightly orange-yellow, dense, soft, malleable, and ductile metal in a pure form. Chemically, gold is a transition metal and a group 11 element. It is one of the least reactive chemical elements and is solid under standard conditions. Gold often occurs in free elemental ( native state), as nuggets or grains, in rocks, veins, and alluvial deposits. It occurs in a solid solution series with the native element silver (as 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 most acids, though it does dissolve in aqua regia (a mixture of nitric acid and hydrochloric acid), forming a soluble tetrachloro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nine (purity)
Nines are an informal, logarithmic notation for proportions very near to one, or equivalently percentages very near 100%. Their common uses include grading the purity of materials. Put simply, "nines" are the number of consecutive nines in a percentage such as 99% (two nines) or a decimal fraction such as 0.999 (three nines). The number of nines of a proportion is \mathrm = -\log_(1-x) However, there are different conventions for stating a non-integer number of nines. 99.5% could be expressed as "two nines five" or 2.3 nines, as outlined below. A completely pure material ( = 1) would have an infinite number of nines. Precious metals The exact purity of very fine precious metals such as platinum, gold and silver can be of great interest. Based on the system of millesimal fineness, a metal is said to be ''one nine'' or ''one nine fine'' if it is 900 fine, or 90% pure. A metal that is 990 fine is then described as ''two nines fine'' and one that is 999 fine is described as ''thre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sterling Silver
Sterling silver is an alloy of silver containing 92.5% by weight of silver and 7.5% by weight of other metals, usually copper. The sterling silver standard has a minimum millesimal fineness of 925. '' Fine silver'', which is 99.9% pure silver, is relatively soft, so silver is usually alloyed with copper to increase its hardness and strength. Sterling silver is prone to tarnishing, and elements other than copper can be used in alloys to reduce tarnishing, as well as casting porosity and firescale. Such elements include germanium, zinc, platinum, silicon, and boron. Recent examples of these alloys include ''argentium'', ''sterlium'' and ''silvadium''. Etymology One of the earliest attestations of the term is in Old French form , in a charter of the abbey of Les Préaux, dating to either 1085 or 1104. The English chronicler Orderic Vitalis (1075 – 1142) uses the Latin forms and . The word in origin refers to the newly introduced Norman silver penny. According to the Oxford En ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sovereign (British Coin)
The sovereign is a British gold coin with a nominal value of one pound sterling (£1) and contains 0.2354 troy oz of pure gold. Struck since 1817, it was originally a circulating coin that was accepted in Britain and elsewhere in the world; it is now a bullion coin and is sometimes mounted in jewellery. In addition, circulation strikes and proof examples are often collected for their numismatic value. In most recent years, it has borne the design of Saint George and the Dragon on the reverse; the initials () of the designer, Benedetto Pistrucci, are visible to the right of the date. The coin was named after the English gold sovereign, which was last minted about 1603, and originated as part of the Great Recoinage of 1816. Many in Parliament believed a one-pound coin should be issued rather than the 21-shilling guinea that was struck until that time. The Master of the Mint, William Wellesley Pole had Pistrucci design the new coin; his depiction was also used for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eagle (United States Coin)
The eagle was a United States $10 gold coin issued by the United States Mint from 1792 to 1933. The eagle was the largest of the five main decimal base-units of denomination used for circulating coinage in the United States prior to 1933, the year when gold was withdrawn from circulation. These five main base-units of denomination were the mill, the cent, the dime, the dollar, and the eagle, where a cent is 10 mills, a dime is 10 cents, a dollar is 10 dimes, and an eagle is 10 dollars. The eagle base-unit of denomination served as the basis of the quarter eagle ($2.50), half eagle ($5), eagle ($10), and double eagle ($20) coins. With the exceptions of the gold dollar coin, the gold three-dollar coin, the three-cent nickel, and the five-cent nickel, the unit of denomination of coinage prior to 1933 was conceptually linked to the precious or semi-precious metal that constituted a majority of the alloy used in that coin. In this regard the United States followed long-standing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Canadian Mint
}) is the mint of Canada and a Crown corporation, operating under the ''Royal Canadian Mint Act''. The shares of the Mint are held in trust for the Crown in right of Canada. The Mint produces all of Canada's circulation coins, and manufactures circulation coins on behalf of other nations. The Mint also designs and manufactures precious and base metal collector coins; gold, silver, palladium, and platinum bullion coins; medals, as well as medallions and tokens. It further offers gold and silver refinery and assay services. The Mint serves the public's interest but is also mandated to operate "in anticipation of profit" (i.e., to function in a commercial manner without relying on taxpayer support to fund its operations). Like private-sector companies, the Mint has a board of directors consisting of a chair, the president and CEO of the Mint, and eight other directors. Traditionally, the president of the Royal Canadian Mint is known as the Master of the Mint, currently ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canadian Gold Maple Leaf
The Canadian Gold Maple Leaf (GML) is a gold bullion coin that is issued annually by the Government of Canada. It is produced by the Royal Canadian Mint. The Gold Maple Leaf is legal tender with a face value of 50 Canadian dollars. The market value of the metal varies, depending on the spot price of gold. Having a .9999 millesimal fineness (24 carats), in some cases .99999, the coin is among the purest official bullion coins worldwide. The standard version has a weight of minimum 1 troy ounce (31.10 grams). Other sizes and denominations include 1 gram, ($0.50), ($1), ($5), ($10), and ($20). The Gold Maple Leaf's obverse and reverse display, respectively, the profile of Queen Elizabeth II of Canada and the Canadian Maple Leaf. In 2013 and 2015, new security features were introduced. In 2013, a laser-micro-engraved textured maple leaf was added on a small area of the reverse (Maple Leaf) side of the coin. In the centre of this mark is the numeral denoting the coin's y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver Coin
Silver coins are considered the oldest mass-produced form of coinage. Silver has been used as a coinage metal since the times of the Greeks; their silver drachmas were popular trade coins. The ancient Persians used silver coins between 612–330 BC. Before 1797, British pennies were made of silver. As with all collectible coins, many factors determine the value of a silver coin, such as its rarity, demand, condition and the number originally minted. Ancient silver coins coveted by collectors include the Denarius and Miliarense, while more recent collectible silver coins include the Morgan Dollar and the Spanish Milled Dollar. Other than collector's silver coins, silver bullion coins are popular among people who desire a "hedge" against currency inflation or store of value. Silver has an international currency symbol of XAG under ISO 4217. Origins and early development of silver coins The earliest coins in the world were minted in the kingdom of Lydia in Asia Minor aroun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Silver
Silver is a chemical element with the symbol Ag (from the Latin ', derived from the Proto-Indo-European ''h₂erǵ'': "shiny" or "white") and atomic number 47. A soft, white, lustrous transition metal, it exhibits the highest electrical conductivity, thermal conductivity, and reflectivity of any metal. The metal is found in the Earth's crust in the pure, free elemental form ("native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a byproduct of copper, gold, lead, and zinc refining. Silver has long been valued as a precious metal. Silver metal is used in many bullion coins, sometimes alongside gold: while it is more abundant than gold, it is much less abundant as a native metal. Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity, silver has had an enduring role in most human cultures. Oth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
