Production
Main articles: Gold prospecting, Gold mining, and Gold extraction
World gold production trend
Gold output in 2005
The entrance to an underground gold mine in Victoria, Australia
Pure gold precipitate produced by the aqua regia refining process
Gold extraction is most economical in large, easily mined deposits. Ore grades as little as 0.5 mg/kg (0.5 parts per million, ppm) can be economical. Typical ore grades in open-pit mines are 1–5 mg/kg (1–5 ppm); ore grades in underground or hard rock mines are usually at least 3 mg/kg (3 ppm). Because ore grades of 30 mg/kg (30 ppm) are usually needed before gold is visible to the naked eye, in most gold mines the gold is invisible.
Since the 1880s, South Africa has been the source for a large proportion of the world's gold supply, with about 50% of all gold ever produced having come from South Africa. Production in 1970 accounted for 79% of the world supply, producing about 1,480 tonnes. 2008 production was 2,260 tonnes. In 2007 China (with 276 tonnes) overtook South Africa as the world's largest gold producer, the first time since 1905 that South Africa has not been the largest.[48]
The city of Johannesburg located in South Africa was founded as a result of the Witwatersrand Gold Rush which resulted in the discovery of some of the largest gold deposits the world has ever seen. Gold fields located within the basin in the Free State and Gauteng provinces are extensive in strike and dip requiring some of the world's deepest mines, with the Savuka and TauTona mines being currently the world's deepest gold mine at 3,777 m. The Second Boer War of 1899–1901 between the British Empire and the Afrikaner Boers was at least partly over the rights of miners and possession of the gold wealth in South Africa.
Other major producers are the United States, Australia, Russia and Peru. Mines in South Dakota and Nevada supply two-thirds of gold used in the United States. In South America, the controversial project Pascua Lama aims at exploitation of rich fields in the high mountains of Atacama Desert, at the border between Chile and Argentina. Today about one-quarter of the world gold output is estimated to originate from artisanal or small scale mining.[49]
After initial production, gold is often subsequently refined industrially by the Wohlwill process which is based on electrolysis or by the Miller process, that is chlorination in the melt. The Wohlwill process results in higher purity, but is more complex and is only applied in small-scale installations.[50][51] Other methods of assaying and purifying smaller amounts of gold include parting and inquartation as well as cupellation, or refining methods based on the dissolution of gold in aqua regia.[52]
At the end of 2009, it was estimated that all the gold ever mined totaled 165,000 tonnes[1] This can be represented by a cube with an edge length of about 20.28 meters. The value of this is very limited; at $1200 per ounce, 165,000 tons of gold would have a value of only 6.6 trillion dollars.
The average gold mining and extraction costs were about US$317/oz in 2007, but these can vary widely depending on mining type and ore quality; global mine production amounted to 2,471.1 tonnes.[53]
Gold is so stable and so valuable that most of the gold used in manufactured goods, jewelry, and works of art is eventually recovered and recycled. Some gold used in spacecraft and electronic equipment cannot be profitably recovered, but it is generally used in these applications in the form of extremely thin layers or extremely fine wires so that the total quantity used (and lost) is small compared to the total amount of gold produced and stockpiled. Thus there is little true consumption of new gold in the economic sense; the stock of gold remains essentially constant (at least in the modern world) while ownership shifts from one party to another.[54] One estimate is that 85% of all the gold ever mined is still available in the world's easily recoverable stocks, with 15% having been lost, or used in non-recyclable industrial uses.[55]
Consumption
The consumption of gold produced in the world is about 50% in jewelry, 40% in investments, and 10% in industry.
India is the world's largest single consumer of gold, as Indians buy about 25% of the world's gold,[56] purchasing approximately 800 tonnes of gold every year, mostly for jewelry. India is also the largest importer gold; in 2008, India imported around 400 tonnes of gold.[57]
Chemistry
Gold (III) chloride solution in water
Although gold is a noble metal, it forms many and diverse compounds. The oxidation state of gold in its compounds ranges from −1 to +5, but Au(I) and Au(III) dominate its chemistry. Au(I), referred to as the aurous ion, is the most common oxidation state with soft ligands such as thioethers, thiolates, and tertiary phosphines. Au(I) compounds are typically linear. A good example is Au(CN)2−, which is the soluble form of gold encountered in mining. Curiously, aurous complexes of water are rare. The binary gold halides, such as AuCl, form zigzag polymeric chains, again featuring linear coordination at Au. Most drugs based on gold are Au(I) derivatives.[58]
Au(III) (auric) is a common oxidation state, and is illustrated by gold(III) chloride, Au2Cl6. The gold atom centers in Au(III) complexes, like other d8 compounds, are typically square planar, with chemical bonds that have both covalent and ionic character.
Aqua regia, a 1:3 mixture of nitric acid and hydrochloric acid, dissolves gold. Nitric acid oxidizes the metal to +3 ions, but only in minute amounts, typically undetectable in the pure acid because of the chemical equilibrium of the reaction. However, the ions are removed from the equilibrium by hydrochloric acid, forming AuCl4− ions, or chloroauric acid, thereby enabling further oxidation.
Some free halogens react with gold.[59] Gold also reacts in alkaline solutions of potassium cyanide. With mercury, it forms an amalgam.
Less common oxidation states
Less common oxidation states of gold include −1, +2, and +5.
The −1 oxidation state occurs in compounds containing the Au− anion, called aurides. Caesium auride (CsAu), for example, crystallizes in the caesium chloride motif.[60] Other aurides include those of Rb+, K+, and tetramethylammonium (CH3)4N+.[61]
Gold(II) compounds are usually diamagnetic with Au–Au bonds such as [Au(CH2)2P(C6H5)2]2Cl2. The evaporation of a solution of Au(OH)3 in concentrated H2SO4 produces red crystals of gold(II) sulfate, AuSO4. Originally thought to be a mixed-valence compound, it has been shown to contain Au4+2 cations.[62][63] A noteworthy, legitimate gold(II) complex is the tetraxenonogold(II) cation, which contains xenon as a ligand, found in [AuXe4](Sb2F11)2.[64]
Gold pentafluoride and its derivative anion, AuF−6, is the sole example of gold(V), the highest verified oxidation state.[65]
Some gold compounds exhibit aurophilic bonding, which describes the tendency of gold ions to interact at distances that are too long to be a conventional Au–Au bond but shorter that van der Waals bonding. The interaction is estimated to be comparable in strength to that of a hydrogen bond.
Mixed valence compounds
Well-defined cluster compounds are numerous.[61] In such cases, gold has a fractional oxidation state. A representative example is the octahedral species {Au(P(C6H5)3)}62+. Gold chalcogenides, such as gold sulfide, feature equal amounts of Au(I) and Au(III).
Toxicity
Pure metallic (elemental) gold is non-toxic and non-irritating when ingested[66] and is sometimes used as a food decoration in the form of gold leaf. Metallic gold is also a component of the alcoholic drinks Goldschläger, Gold Strike, and Goldwasser. Metallic gold is approved as a food additive in the EU (E175 in the Codex Alimentarius). Although gold ion is toxic, the acceptance of metallic gold as a food additive is due to its relative chemical inertness, and resistance to being corroded or transformed into soluble salts (gold compounds) by any known chemical process which would be encountered in the human body.
Soluble compounds (gold salts) such as gold chloride are toxic to the liver and kidneys. Common cyanide salts of gold such as potassium gold cyanide, used in gold electroplating, are toxic both by virtue of their cyanide and gold content. There are rare cases of lethal gold poisoning from potassium gold cyanide.[67][68] Gold toxicity can be ameliorated with chelation therapy with an agent such as Dimercaprol.
Gold metal was voted Allergen of the Year in 2001 by the American Contact Dermatitis Society. Gold contact allergies affect mostly women.[69] Despite this, gold is a relatively non-potent contact allergen, in comparison with metals like nickel.[70]
Price
Gold price per troy ounce in USD since 1960, in nominal US$ (black) and in 2009 US$ (red) after inflation adjustment using the CPI-U price index.
Like other precious metals, gold is measured by troy weight and by grams. When it is alloyed with other metals the term carat or karat is used to indicate the amount of gold present, with 24 carats being pure gold and lower ratings proportionally less. The purity of a gold bar or coin can also be expressed as a decimal figure ranging from 0 to 1, known as the millesimal fineness, such as 0.995 being very pure.
The price of gold is determined through trading in the gold and derivatives markets, but a procedure known as the Gold Fixing in London, originating in September 1919, provides a daily benchmark price to the industry. The afternoon fixing was introduced in 1968 to provide a price when US markets are open.
Historically gold coinage was widely used as currency; when paper money was introduced, it typically was a receipt redeemable for gold coin or bullion. In a monetary system known as the gold standard, a certain weight of gold was given the name of a unit of currency. For a long period, the United States government set the value of the US dollar so that one troy ounce was equal to $20.67 ($664.56/kg), but in 1934 the dollar was devalued to $35.00 per troy ounce ($1125.27/kg). By 1961, it was becoming hard to maintain this price, and a pool of US and European banks agreed to manipulate the market to prevent further currency devaluation against increased gold demand.
Swiss-cast 1 kg gold bar
On March 17, 1968, economic circumstances caused the collapse of the gold pool, and a two-tiered pricing scheme was established whereby gold was still used to settle international accounts at the old $35.00 per troy ounce ($1.13/g) but the price of gold on the private market was allowed to fluctuate; this two-tiered pricing system was abandoned in 1975 when the price of gold was left to find its free-market level. Central banks still hold historical gold reserves as a store of value although the level has generally been declining. The largest gold depository in the world is that of the U.S. Federal Reserve Bank in New York, which holds about 3%[citation needed] of the gold ever mined, as does the similarly laden U.S. Bullion Depository at Fort Knox.
In 2005 the World Gold Council estimated total global gold supply to be 3,859 tonnes and demand to be 3,754 tonnes, giving a surplus of 105 tonnes.[71]
Since 1968 the price of gold has ranged widely, from a high of $850/oz ($27,300/kg) on January 21, 1980, to a low of $252.90/oz ($8,131/kg) on June 21, 1999 (London Gold Fixing).[72] The period from 1999 to 2001 marked the "Brown Bottom" after a 20-year bear market.[73] Prices increased rapidly from 1991, but the 1980 high was not exceeded until January 3, 2008 when a new maximum of $865.35 per troy ounce was set (a.m. London Gold Fixing).[74] Another record price was set on March 17, 2008 at $1023.50/oz ($32,900/kg)(am. London Gold Fixing).[74] In the fall of 2009, gold markets experienced renewed momentum upwards due to increased demand and a weakening US dollar. On December 2, 2009, Gold passed the important barrier of US$1200 per ounce to close at $1215.[75] Gold further rallied hitting new highs in May 2010 after the European Union debt crisis prompted further purchase of gold as a safe asset.[76][77]
Since April 2001 the gold price has more than tripled in value against the US dollar,[78] prompting speculation that this long secular bear market has ended and a bull market has returned.[79]
Symbolism
Gold bars at the Emperor Casino in Macau
Gold has been highly valued in many societies throughout the ages. In keeping with this it has often had a strongly positive symbolic meaning closely connected to the values held in the highest esteem in the society in question. Gold may symbolize power, strength, wealth, warmth, happiness, love, hope, optimism, intelligence, justice, balance, perfection, summer, harvest and the sun.
Great human achievements are frequently rewarded with gold, in the form of gold medals, golden trophies and other decorations. Winners of athletic events and other graded competitions are usually awarded a gold medal (e.g., the Olympic Games). Many awards such as the Nobel Prize are made from gold as well. Other award statues and prizes are depicted in gold or are gold plated (such as the Academy Awards, the Golden Globe Awards, the Emmy Awards, the Palme d'Or, and the British Academy Film Awards).
Aristotle in his ethics used gold symbolism when referring to what is now commonly known as the "golden mean". Similarly, gold is associated with perfect or divine principles, such as in the case of Phi, which is sometimes called the "golden ratio".
Gold represents great value. Respected people are treated with the most valued rule, the "golden rule". A company may give its most valued customers "gold cards" or make them "gold members". We value moments of peace and therefore we say: "silence is golden". In Greek mythology there was the "golden fleece".
Gold is further associated with the wisdom of aging and fruition. The fiftieth wedding anniversary is golden. Our precious latter years are sometimes considered "golden years". The height of a civilization is referred to as a "golden age".
In Christianity gold has sometimes been associated with the extremities of utmost evil and the greatest sanctity. In the Book of Exodus, the Golden Calf is a symbol of idolatry. In the Book of Genesis, Abraham was said to be rich in gold and silver, and Moses was instructed to cover the Mercy Seat of the Ark of the Covenant with pure gold. In Christian art the halos of Christ, Mary and the Christian saints are golden.
Medieval kings were inaugurated under the signs of sacred oil and a golden crown, the latter symbolizing the eternal shining light of heaven and thus a Christian king's divinely inspired authority. Wedding rings have long been made of gold. It is long lasting and unaffected by the passage of time and may aid in the ring symbolism of eternal vows before God and/or the sun and moon and the perfection the marriage signifies. In Orthodox Christianity, the wedded couple is adorned with a golden crown during the ceremony, an amalgamation of symbolic rites.
In popular culture gold holds many connotations but is most generally connected to terms such as good or great, such as in the phrases: "has a heart of gold", "that's golden!", "golden moment", "then you're golden!" and "golden boy". Gold also still holds its place as a symbol of wealth and through that, in many societies, success.
State emblem
In 1965, the California Legislature designated gold "the State Mineral and mineralogical emblem."[80]
In 1968, the Alaska Legislature named gold "the official state mineral."[81]
See also
* Altai Mountains
* Commodity fetishism (Marxist economic theory)
* Digital gold currency
* Gold Anti-Trust Action Committee
* Gold bubble
* Gold fingerprinting
* Gold Prospectors Association of America
* Gold standard
* Mining in Roman Britain
* Prospecting
* Roman engineering
* Tumbaga
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External links
Wikimedia Commons has media related to: Gold
Look up gold in Wiktionary, the free dictionary.
* Getting Gold 1898 book, www.lateralscience.co.uk
* Technical Document on Extraction and Mining of Gold, www.epa.gov
* Picture in the Element collection from Heinrich Pniok, www.pniok.de
* WebElements.com — Gold n www.webelements.com
* Chemistry in its element podcast (MP3) from the Royal Society of Chemistry's Chemistry World: Gold www.rsc.org
Read more: http://www.answers.com/topic/gold#ixzz18dFGmeyZ
Main articles: Gold prospecting, Gold mining, and Gold extraction
World gold production trend
Gold output in 2005
The entrance to an underground gold mine in Victoria, Australia
Pure gold precipitate produced by the aqua regia refining process
Gold extraction is most economical in large, easily mined deposits. Ore grades as little as 0.5 mg/kg (0.5 parts per million, ppm) can be economical. Typical ore grades in open-pit mines are 1–5 mg/kg (1–5 ppm); ore grades in underground or hard rock mines are usually at least 3 mg/kg (3 ppm). Because ore grades of 30 mg/kg (30 ppm) are usually needed before gold is visible to the naked eye, in most gold mines the gold is invisible.
Since the 1880s, South Africa has been the source for a large proportion of the world's gold supply, with about 50% of all gold ever produced having come from South Africa. Production in 1970 accounted for 79% of the world supply, producing about 1,480 tonnes. 2008 production was 2,260 tonnes. In 2007 China (with 276 tonnes) overtook South Africa as the world's largest gold producer, the first time since 1905 that South Africa has not been the largest.[48]
The city of Johannesburg located in South Africa was founded as a result of the Witwatersrand Gold Rush which resulted in the discovery of some of the largest gold deposits the world has ever seen. Gold fields located within the basin in the Free State and Gauteng provinces are extensive in strike and dip requiring some of the world's deepest mines, with the Savuka and TauTona mines being currently the world's deepest gold mine at 3,777 m. The Second Boer War of 1899–1901 between the British Empire and the Afrikaner Boers was at least partly over the rights of miners and possession of the gold wealth in South Africa.
Other major producers are the United States, Australia, Russia and Peru. Mines in South Dakota and Nevada supply two-thirds of gold used in the United States. In South America, the controversial project Pascua Lama aims at exploitation of rich fields in the high mountains of Atacama Desert, at the border between Chile and Argentina. Today about one-quarter of the world gold output is estimated to originate from artisanal or small scale mining.[49]
After initial production, gold is often subsequently refined industrially by the Wohlwill process which is based on electrolysis or by the Miller process, that is chlorination in the melt. The Wohlwill process results in higher purity, but is more complex and is only applied in small-scale installations.[50][51] Other methods of assaying and purifying smaller amounts of gold include parting and inquartation as well as cupellation, or refining methods based on the dissolution of gold in aqua regia.[52]
At the end of 2009, it was estimated that all the gold ever mined totaled 165,000 tonnes[1] This can be represented by a cube with an edge length of about 20.28 meters. The value of this is very limited; at $1200 per ounce, 165,000 tons of gold would have a value of only 6.6 trillion dollars.
The average gold mining and extraction costs were about US$317/oz in 2007, but these can vary widely depending on mining type and ore quality; global mine production amounted to 2,471.1 tonnes.[53]
Gold is so stable and so valuable that most of the gold used in manufactured goods, jewelry, and works of art is eventually recovered and recycled. Some gold used in spacecraft and electronic equipment cannot be profitably recovered, but it is generally used in these applications in the form of extremely thin layers or extremely fine wires so that the total quantity used (and lost) is small compared to the total amount of gold produced and stockpiled. Thus there is little true consumption of new gold in the economic sense; the stock of gold remains essentially constant (at least in the modern world) while ownership shifts from one party to another.[54] One estimate is that 85% of all the gold ever mined is still available in the world's easily recoverable stocks, with 15% having been lost, or used in non-recyclable industrial uses.[55]
Consumption
The consumption of gold produced in the world is about 50% in jewelry, 40% in investments, and 10% in industry.
India is the world's largest single consumer of gold, as Indians buy about 25% of the world's gold,[56] purchasing approximately 800 tonnes of gold every year, mostly for jewelry. India is also the largest importer gold; in 2008, India imported around 400 tonnes of gold.[57]
Chemistry
Gold (III) chloride solution in water
Although gold is a noble metal, it forms many and diverse compounds. The oxidation state of gold in its compounds ranges from −1 to +5, but Au(I) and Au(III) dominate its chemistry. Au(I), referred to as the aurous ion, is the most common oxidation state with soft ligands such as thioethers, thiolates, and tertiary phosphines. Au(I) compounds are typically linear. A good example is Au(CN)2−, which is the soluble form of gold encountered in mining. Curiously, aurous complexes of water are rare. The binary gold halides, such as AuCl, form zigzag polymeric chains, again featuring linear coordination at Au. Most drugs based on gold are Au(I) derivatives.[58]
Au(III) (auric) is a common oxidation state, and is illustrated by gold(III) chloride, Au2Cl6. The gold atom centers in Au(III) complexes, like other d8 compounds, are typically square planar, with chemical bonds that have both covalent and ionic character.
Aqua regia, a 1:3 mixture of nitric acid and hydrochloric acid, dissolves gold. Nitric acid oxidizes the metal to +3 ions, but only in minute amounts, typically undetectable in the pure acid because of the chemical equilibrium of the reaction. However, the ions are removed from the equilibrium by hydrochloric acid, forming AuCl4− ions, or chloroauric acid, thereby enabling further oxidation.
Some free halogens react with gold.[59] Gold also reacts in alkaline solutions of potassium cyanide. With mercury, it forms an amalgam.
Less common oxidation states
Less common oxidation states of gold include −1, +2, and +5.
The −1 oxidation state occurs in compounds containing the Au− anion, called aurides. Caesium auride (CsAu), for example, crystallizes in the caesium chloride motif.[60] Other aurides include those of Rb+, K+, and tetramethylammonium (CH3)4N+.[61]
Gold(II) compounds are usually diamagnetic with Au–Au bonds such as [Au(CH2)2P(C6H5)2]2Cl2. The evaporation of a solution of Au(OH)3 in concentrated H2SO4 produces red crystals of gold(II) sulfate, AuSO4. Originally thought to be a mixed-valence compound, it has been shown to contain Au4+2 cations.[62][63] A noteworthy, legitimate gold(II) complex is the tetraxenonogold(II) cation, which contains xenon as a ligand, found in [AuXe4](Sb2F11)2.[64]
Gold pentafluoride and its derivative anion, AuF−6, is the sole example of gold(V), the highest verified oxidation state.[65]
Some gold compounds exhibit aurophilic bonding, which describes the tendency of gold ions to interact at distances that are too long to be a conventional Au–Au bond but shorter that van der Waals bonding. The interaction is estimated to be comparable in strength to that of a hydrogen bond.
Mixed valence compounds
Well-defined cluster compounds are numerous.[61] In such cases, gold has a fractional oxidation state. A representative example is the octahedral species {Au(P(C6H5)3)}62+. Gold chalcogenides, such as gold sulfide, feature equal amounts of Au(I) and Au(III).
Toxicity
Pure metallic (elemental) gold is non-toxic and non-irritating when ingested[66] and is sometimes used as a food decoration in the form of gold leaf. Metallic gold is also a component of the alcoholic drinks Goldschläger, Gold Strike, and Goldwasser. Metallic gold is approved as a food additive in the EU (E175 in the Codex Alimentarius). Although gold ion is toxic, the acceptance of metallic gold as a food additive is due to its relative chemical inertness, and resistance to being corroded or transformed into soluble salts (gold compounds) by any known chemical process which would be encountered in the human body.
Soluble compounds (gold salts) such as gold chloride are toxic to the liver and kidneys. Common cyanide salts of gold such as potassium gold cyanide, used in gold electroplating, are toxic both by virtue of their cyanide and gold content. There are rare cases of lethal gold poisoning from potassium gold cyanide.[67][68] Gold toxicity can be ameliorated with chelation therapy with an agent such as Dimercaprol.
Gold metal was voted Allergen of the Year in 2001 by the American Contact Dermatitis Society. Gold contact allergies affect mostly women.[69] Despite this, gold is a relatively non-potent contact allergen, in comparison with metals like nickel.[70]
Price
Gold price per troy ounce in USD since 1960, in nominal US$ (black) and in 2009 US$ (red) after inflation adjustment using the CPI-U price index.
Like other precious metals, gold is measured by troy weight and by grams. When it is alloyed with other metals the term carat or karat is used to indicate the amount of gold present, with 24 carats being pure gold and lower ratings proportionally less. The purity of a gold bar or coin can also be expressed as a decimal figure ranging from 0 to 1, known as the millesimal fineness, such as 0.995 being very pure.
The price of gold is determined through trading in the gold and derivatives markets, but a procedure known as the Gold Fixing in London, originating in September 1919, provides a daily benchmark price to the industry. The afternoon fixing was introduced in 1968 to provide a price when US markets are open.
Historically gold coinage was widely used as currency; when paper money was introduced, it typically was a receipt redeemable for gold coin or bullion. In a monetary system known as the gold standard, a certain weight of gold was given the name of a unit of currency. For a long period, the United States government set the value of the US dollar so that one troy ounce was equal to $20.67 ($664.56/kg), but in 1934 the dollar was devalued to $35.00 per troy ounce ($1125.27/kg). By 1961, it was becoming hard to maintain this price, and a pool of US and European banks agreed to manipulate the market to prevent further currency devaluation against increased gold demand.
Swiss-cast 1 kg gold bar
On March 17, 1968, economic circumstances caused the collapse of the gold pool, and a two-tiered pricing scheme was established whereby gold was still used to settle international accounts at the old $35.00 per troy ounce ($1.13/g) but the price of gold on the private market was allowed to fluctuate; this two-tiered pricing system was abandoned in 1975 when the price of gold was left to find its free-market level. Central banks still hold historical gold reserves as a store of value although the level has generally been declining. The largest gold depository in the world is that of the U.S. Federal Reserve Bank in New York, which holds about 3%[citation needed] of the gold ever mined, as does the similarly laden U.S. Bullion Depository at Fort Knox.
In 2005 the World Gold Council estimated total global gold supply to be 3,859 tonnes and demand to be 3,754 tonnes, giving a surplus of 105 tonnes.[71]
Since 1968 the price of gold has ranged widely, from a high of $850/oz ($27,300/kg) on January 21, 1980, to a low of $252.90/oz ($8,131/kg) on June 21, 1999 (London Gold Fixing).[72] The period from 1999 to 2001 marked the "Brown Bottom" after a 20-year bear market.[73] Prices increased rapidly from 1991, but the 1980 high was not exceeded until January 3, 2008 when a new maximum of $865.35 per troy ounce was set (a.m. London Gold Fixing).[74] Another record price was set on March 17, 2008 at $1023.50/oz ($32,900/kg)(am. London Gold Fixing).[74] In the fall of 2009, gold markets experienced renewed momentum upwards due to increased demand and a weakening US dollar. On December 2, 2009, Gold passed the important barrier of US$1200 per ounce to close at $1215.[75] Gold further rallied hitting new highs in May 2010 after the European Union debt crisis prompted further purchase of gold as a safe asset.[76][77]
Since April 2001 the gold price has more than tripled in value against the US dollar,[78] prompting speculation that this long secular bear market has ended and a bull market has returned.[79]
Symbolism
Gold bars at the Emperor Casino in Macau
Gold has been highly valued in many societies throughout the ages. In keeping with this it has often had a strongly positive symbolic meaning closely connected to the values held in the highest esteem in the society in question. Gold may symbolize power, strength, wealth, warmth, happiness, love, hope, optimism, intelligence, justice, balance, perfection, summer, harvest and the sun.
Great human achievements are frequently rewarded with gold, in the form of gold medals, golden trophies and other decorations. Winners of athletic events and other graded competitions are usually awarded a gold medal (e.g., the Olympic Games). Many awards such as the Nobel Prize are made from gold as well. Other award statues and prizes are depicted in gold or are gold plated (such as the Academy Awards, the Golden Globe Awards, the Emmy Awards, the Palme d'Or, and the British Academy Film Awards).
Aristotle in his ethics used gold symbolism when referring to what is now commonly known as the "golden mean". Similarly, gold is associated with perfect or divine principles, such as in the case of Phi, which is sometimes called the "golden ratio".
Gold represents great value. Respected people are treated with the most valued rule, the "golden rule". A company may give its most valued customers "gold cards" or make them "gold members". We value moments of peace and therefore we say: "silence is golden". In Greek mythology there was the "golden fleece".
Gold is further associated with the wisdom of aging and fruition. The fiftieth wedding anniversary is golden. Our precious latter years are sometimes considered "golden years". The height of a civilization is referred to as a "golden age".
In Christianity gold has sometimes been associated with the extremities of utmost evil and the greatest sanctity. In the Book of Exodus, the Golden Calf is a symbol of idolatry. In the Book of Genesis, Abraham was said to be rich in gold and silver, and Moses was instructed to cover the Mercy Seat of the Ark of the Covenant with pure gold. In Christian art the halos of Christ, Mary and the Christian saints are golden.
Medieval kings were inaugurated under the signs of sacred oil and a golden crown, the latter symbolizing the eternal shining light of heaven and thus a Christian king's divinely inspired authority. Wedding rings have long been made of gold. It is long lasting and unaffected by the passage of time and may aid in the ring symbolism of eternal vows before God and/or the sun and moon and the perfection the marriage signifies. In Orthodox Christianity, the wedded couple is adorned with a golden crown during the ceremony, an amalgamation of symbolic rites.
In popular culture gold holds many connotations but is most generally connected to terms such as good or great, such as in the phrases: "has a heart of gold", "that's golden!", "golden moment", "then you're golden!" and "golden boy". Gold also still holds its place as a symbol of wealth and through that, in many societies, success.
State emblem
In 1965, the California Legislature designated gold "the State Mineral and mineralogical emblem."[80]
In 1968, the Alaska Legislature named gold "the official state mineral."[81]
See also
* Altai Mountains
* Commodity fetishism (Marxist economic theory)
* Digital gold currency
* Gold Anti-Trust Action Committee
* Gold bubble
* Gold fingerprinting
* Gold Prospectors Association of America
* Gold standard
* Mining in Roman Britain
* Prospecting
* Roman engineering
* Tumbaga
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79. ^ "Gold starts 2006 well, but this is not a 25-year high!". Ameinfo.com. http://www.ameinfo.com/75511.html. Retrieved 2009-04-05.
80. ^ California Government Code selection 420-429.8 (see § 425.1)
81. ^ Alaska Statutes (see§ 44.09.110)
External links
Wikimedia Commons has media related to: Gold
Look up gold in Wiktionary, the free dictionary.
* Getting Gold 1898 book, www.lateralscience.co.uk
* Technical Document on Extraction and Mining of Gold, www.epa.gov
* Picture in the Element collection from Heinrich Pniok, www.pniok.de
* WebElements.com — Gold n www.webelements.com
* Chemistry in its element podcast (MP3) from the Royal Society of Chemistry's Chemistry World: Gold www.rsc.org
Read more: http://www.answers.com/topic/gold#ixzz18dFGmeyZ
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والسلام عليكم ورحمة الله وبركاته
هل تريد ان تمتلك موقع مجانى شاهد مواقعى كلها مجانيه ان اردت مثلها ضع تعليقك بطلبك على المنتدى الاخير فى المواقع المذكوره وسوف اذكر لك طرقة امتلاك هذه المواقع المجانيه لا تتكاسل وكن من اصحاب المواقع
مواقعى هى
عالم الموضه والزياء موقع عالمى مهتم بكل ما هو جديد فى عالم الموضه
https://sites.google.com/site/modah2011
الموقع الثانى باللغه الانجليزيه : موقع الذب والمجوهرات والتجاره الالكترونيه والموضه كل ذالك فى موقع واحد شاهدى واستفادى وبه قسم تعليمى (ferox gold fashion)
https://sites.google.com/site/goldelviroxfashion
الموقع الثالث : موقع الذهب gold gold gold gold وهو موقع مهتم بتطورات الذهب والبورصه
https://sites.google.com/site/projectwik2010/
الموقع الرابع :المجتمع من حولك كل ما يدور فى المجتمع من حولك من احداث واخبار وعالم الانترنت والكمبيوتر والاضرابات والاعتصامات من حولك
وهو موقع يشبه المواقع الاخباريه ولكنه فى مرحلة التطوير وتجد الموقع شكله يتم تطويره
https://sites.google.com/site/medomex22
الموقع الخامس : موقع القرأن الكريم وهو موقع فى حيز التنفيذذ لم تنفذ منه الا الواجهه شاهد
https://sites.google.com/site/coraan2010
المنتدى المجانى الذى يوضع به الطلبات والتعليقات
http://7ayate.forumegypt.net
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