14:45:11 GMT, 15 May, 2007
Record numbers of American Eagle gold coins are being snapped up by investors across the world, the company has announced.American Eagle suggests that this is due to its coins having a high gold content and investors are specifically looking to purchase gold coins in order to acquire a secure investment so that currency fluctuations are offset.Another reason for American Eagle's gold coin success can be attributed to the fact the firm's product is one of the few that are rubber stamped by the US government to guarantee the coins' weight, content and purity.DeMeritt of Lear Financial, the parent company of Gold Central, stated: "This is the best way for the small investor to enter the gold market with an investment in gold coins."Back in 1986 was when American Eagle minted its first gold coin and its 22-carat offerings can now be purchased in one ounce, half ounce, quarter ounce or one tenths of an ounce quantities.
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China's gold production increases in March
12:44:55 GMT, 14 May, 2007
Gold production in China has increased by almost 16 per cent in the first quarter of 2007 compared with the corresponding period for last year.A total of 56.183 tonnes was produced in the first quarter of 2007, explained the China Gold Industry Association, which represents a year-on-year rise of 15.99 per cent.Commenting on the development, Sun Zhaoxue, head of the China Gold Industry Association, stated that the gold industry in his country was currently enjoying something of a rapid growth period.He went on to say that 2006's gold production in China was record-breaking as the country benefited from greater profits and output.Last month, the China Gold Association announced that the quantity of sales in terms of the gold and jewellery markets in China had witnessed a 20 per cent annual rate of growth. This represents a collective total of 1,400 billion Yuan (£92 billion).Additionally, the groundwork has been put in place for the future launch of the China Gold Industry Standardisation Technical Committee.
Gold production in China has increased by almost 16 per cent in the first quarter of 2007 compared with the corresponding period for last year.A total of 56.183 tonnes was produced in the first quarter of 2007, explained the China Gold Industry Association, which represents a year-on-year rise of 15.99 per cent.Commenting on the development, Sun Zhaoxue, head of the China Gold Industry Association, stated that the gold industry in his country was currently enjoying something of a rapid growth period.He went on to say that 2006's gold production in China was record-breaking as the country benefited from greater profits and output.Last month, the China Gold Association announced that the quantity of sales in terms of the gold and jewellery markets in China had witnessed a 20 per cent annual rate of growth. This represents a collective total of 1,400 billion Yuan (£92 billion).Additionally, the groundwork has been put in place for the future launch of the China Gold Industry Standardisation Technical Committee.
China may look to gold acquisition
15:49:29 GMT, 11 May, 2007
China has only a very small proportion of gold accounting for its total reserves in comparison with other countries like the US but the Asian country could soon be about to change this fact.Two weeks ago, the People's Bank of China vice-governor Xiang Junbo, explained that his country's government should take steps to "appropriately increase its gold reserves".At present, Goldseek.com reports that China has 1.3 per cent of its reserves in gold which is dwarfed by the percentage that the US holds (75.9 per cent) as well as the European region which has 24.4 per cent of its reserves being accounted for by gold.Goldseek.com goes on to suggest that China's $1.2 trillion (£605 billion) cash reserves could "soon" be diluted by the acquisition of gold.According to the website, the 1.3 per cent of China's total reserves equates to an accumulation of gold that is 19.29 million ounces and this would represent a $12 billion (£6 billion) stash.
China has only a very small proportion of gold accounting for its total reserves in comparison with other countries like the US but the Asian country could soon be about to change this fact.Two weeks ago, the People's Bank of China vice-governor Xiang Junbo, explained that his country's government should take steps to "appropriately increase its gold reserves".At present, Goldseek.com reports that China has 1.3 per cent of its reserves in gold which is dwarfed by the percentage that the US holds (75.9 per cent) as well as the European region which has 24.4 per cent of its reserves being accounted for by gold.Goldseek.com goes on to suggest that China's $1.2 trillion (£605 billion) cash reserves could "soon" be diluted by the acquisition of gold.According to the website, the 1.3 per cent of China's total reserves equates to an accumulation of gold that is 19.29 million ounces and this would represent a $12 billion (£6 billion) stash.
Coeur d'Alene to buy gold mining firms
13:34:43 GMT, 04 May, 2007
US mining group Coeur D'Alene has announced that it will be purchasing operations in Australia and Mexico totalling some $1.1 billion (£553 million).The group's acquisition of Bolnisi Gold NL and Palmajero Silver and Gold will see the respective operations receiving 0.682 and 2.715 shares for each of their own shares.Bolnisi and Palmajero shareholders will also be receiving three-tenths of a cent per share they own.In order to pay for the deal, which represents the group's first project in Mexico, Coeur d'Alene is mooting the listing of its shares on the Australian Stock Exchange.The transaction is expected to be completed during the third quarter of this year, with Coeur d'Alene also building a gold mine in Alaska.The group also owns three operations in North and South America as well as mineral reserves in Australia.
US mining group Coeur D'Alene has announced that it will be purchasing operations in Australia and Mexico totalling some $1.1 billion (£553 million).The group's acquisition of Bolnisi Gold NL and Palmajero Silver and Gold will see the respective operations receiving 0.682 and 2.715 shares for each of their own shares.Bolnisi and Palmajero shareholders will also be receiving three-tenths of a cent per share they own.In order to pay for the deal, which represents the group's first project in Mexico, Coeur d'Alene is mooting the listing of its shares on the Australian Stock Exchange.The transaction is expected to be completed during the third quarter of this year, with Coeur d'Alene also building a gold mine in Alaska.The group also owns three operations in North and South America as well as mineral reserves in Australia.
Gold price could rise in 2007, says expert
12:27:31 GMT, 02 May, 2007
A "shortage" of gold in China in the "long-term" could have a positive effect on the price of the precious metal this year, according to US gold coin firm Lear Financial's gold investment advisor.Speaking to South African website Business Day, Kevin DeMeritt believes that 2007 has a "good chance" of witnessing a gold price that beats last year's high of $725 (£363) per ounce.Demand for gold is not being matched by supply, however, Lear Financial explained. He also stated that it is currently "difficult" for China to create any kind of "major long-term growth in gold production".Lear Financial went on to state that: "As a long-term solution the world's largest 20 gold producers are combating these critical shortages with increased exploration budgets, but in the short term gold prices will continue to climb."The price of gold can only realistically rise in light of the fact that, according to Lear Financial, demand for jewellery, investments and high-tech industry increases at the same time as "this stronger demand is not being met by worldwide gold producers thanks to declining production - from South Africa in particular."
A "shortage" of gold in China in the "long-term" could have a positive effect on the price of the precious metal this year, according to US gold coin firm Lear Financial's gold investment advisor.Speaking to South African website Business Day, Kevin DeMeritt believes that 2007 has a "good chance" of witnessing a gold price that beats last year's high of $725 (£363) per ounce.Demand for gold is not being matched by supply, however, Lear Financial explained. He also stated that it is currently "difficult" for China to create any kind of "major long-term growth in gold production".Lear Financial went on to state that: "As a long-term solution the world's largest 20 gold producers are combating these critical shortages with increased exploration budgets, but in the short term gold prices will continue to climb."The price of gold can only realistically rise in light of the fact that, according to Lear Financial, demand for jewellery, investments and high-tech industry increases at the same time as "this stronger demand is not being met by worldwide gold producers thanks to declining production - from South Africa in particular."
Yellow gold is in demand
14:39:50 GMT, 18 May, 2007
Jewellers at the international jewellery fair in Vicenza have spoken of their belief that this year promises to see a splurge of demand for yellow gold.Designer Paladino Orlandini stressed to news agency Reuters that yellow gold resonates with a "warm message" to consumers, highlighting its popular place in the jewellery market.In addition, there is currently a tide of demand from Europe and the US for styles of yellow gold jewellery that harps back to by-gone eras such as Roman and Ancient Greek times. Demand for jewellery is up per se, according to the World Gold Council (WGC) which discovered that March this year saw a 38 per cent increase in demand for jewellery worldwide on the corresponding time period last year.The Chinese year of the golden pig has had a positive impact on worldwide sales due to the fact that it is seen as being a highly auspicious period and so gold purchases, especially jewellery have risen as a result.
Jewellers at the international jewellery fair in Vicenza have spoken of their belief that this year promises to see a splurge of demand for yellow gold.Designer Paladino Orlandini stressed to news agency Reuters that yellow gold resonates with a "warm message" to consumers, highlighting its popular place in the jewellery market.In addition, there is currently a tide of demand from Europe and the US for styles of yellow gold jewellery that harps back to by-gone eras such as Roman and Ancient Greek times. Demand for jewellery is up per se, according to the World Gold Council (WGC) which discovered that March this year saw a 38 per cent increase in demand for jewellery worldwide on the corresponding time period last year.The Chinese year of the golden pig has had a positive impact on worldwide sales due to the fact that it is seen as being a highly auspicious period and so gold purchases, especially jewellery have risen as a result.
Gold plated trophy fetches $22k
15:25:44 GMT, 04 May, 2007
An exclusive gold-plated mint julep cup made by Woodford Reserve has fetched $22,000 at a charity auction.The 24-kt gold-plated cup was one of a series commemorating past winners of the Kentucky Derby and bore the name of the 2006 Derby winner, Barbaro.Barbaro won last year's Derby by 6 1/2 lengths but died soon after from laminitis, which caused complications during surgery on a broken leg.The cups raised a combined total of $49,337 in the charity auction with proceeds benefiting retired race horses and injured jockeys.Bonnie O'Neil, who successfully purchased the cup asked Barbaro owner Gretchen Jackson to collect the cup at the 2007 Kentucky Derby, to be held on Saturday May 5th."I wanted to do something in my own little way to make sure Barbaro didn't die in vain," she commented. "I was thrilled when Gretchen Jackson agreed to accept the cup on my behalf."Woodford Reserve is the official bourbon of the Kentucky Derby and created 132 exclusive gold-plated cups, each bearing the name of a past winner.
An exclusive gold-plated mint julep cup made by Woodford Reserve has fetched $22,000 at a charity auction.The 24-kt gold-plated cup was one of a series commemorating past winners of the Kentucky Derby and bore the name of the 2006 Derby winner, Barbaro.Barbaro won last year's Derby by 6 1/2 lengths but died soon after from laminitis, which caused complications during surgery on a broken leg.The cups raised a combined total of $49,337 in the charity auction with proceeds benefiting retired race horses and injured jockeys.Bonnie O'Neil, who successfully purchased the cup asked Barbaro owner Gretchen Jackson to collect the cup at the 2007 Kentucky Derby, to be held on Saturday May 5th."I wanted to do something in my own little way to make sure Barbaro didn't die in vain," she commented. "I was thrilled when Gretchen Jackson agreed to accept the cup on my behalf."Woodford Reserve is the official bourbon of the Kentucky Derby and created 132 exclusive gold-plated cups, each bearing the name of a past winner.
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Gold
Gold (IPA: /ˈgold/) is a chemical element with the symbol Au (from the Latin aurum) and atomic number 79. It is a highly sought-after precious metal which, for many centuries, has been used as money, a store of value and in jewelery. The metal occurs as nuggets or grains in rocks, underground "veins" and in alluvial deposits. It is one of the coinage metals. It is a dense, soft, shiny, yellow metal, and is the most malleable and ductile of the known metals.
Gold forms the basis for a monetary standard used by the International Monetary Fund (IMF) and the Bank for International Settlements (BIS). Its ISO currency code is XAU. Modern industrial uses include dentistry and electronics, where gold has traditionally found use because of its good resistance to oxidative corrosion.
Chemically, gold is a trivalent and univalent transition metal. Gold does not react with most chemicals, but is attacked by chlorine, fluorine, aqua regia and cyanide. Gold dissolves in mercury, forming amalgam alloys. In particular, gold is insoluble in nitric acid, which will dissolve most other metals. Nitric acid has long been used to confirm the presence of gold in items, and this is the origin of the colloquial term "acid test," referring to a gold standard test for genuine value.
Contents[hide]
1 Characteristics
1.1 Toxicity
2 Applications
2.1 As the metal
2.2 As gold chemical compounds
3 History
4 Production
5 Price
6 Compounds
6.1 Less common oxidation states: Au(-I), Au(II), and Au(V)
6.2 Mixed valence compounds
7 Isotopes
8 Symbolism
9 References
10 See also
11 External links
//
Characteristics
Gold is the most malleable and ductile metal; a single gram can be beaten into a sheet of one square meter, or an ounce into 300 square feet. Gold readily forms alloys with many other metals. These alloys can be produced to increase the hardness or to create exotic colors. Adding copper yields a redder metal, iron blue, aluminium purple, platinum white, and natural bismuth and silver alloys produce black. Native gold contains usually eight to ten percent silver, but often much more — alloys with a silver content over 20% are called electrum. As the amount of silver increases, the color becomes whiter and the specific gravity becomes lower.
Gold is a good conductor of heat and electricity, and is not affected by air and most reagents. Heat, moisture, oxygen, and most corrosive agents have very little chemical effect on gold, making it well-suited for use in coins and jewelry; conversely, halogens will chemically alter gold, and aqua regia dissolves it by virtue of the elemental chlorine generated by this acid mixture.
Common oxidation states of gold include +1 (gold(I) or aurous compounds) and +3 (gold(III) or auric compounds). Gold ions in solution are readily reduced and precipitated out as gold metal by adding any other metal as the reducing agent. The added metal is oxidized and dissolves allowing the gold to be displaced from solution and be recovered as a solid precipitate.
Recent research undertaken by Sir Frank Reith of the Australian National University shows that microbes play an important role in forming gold deposits, transporting and precipitating gold to form grains and nuggets that collect in alluvial deposits.[1]
High quality pure metallic gold is tasteless, in keeping with its resistance to corrosion (it is metal ions which confer taste to metals).
In addition, gold is very dense, a cubic meter weighing 19300 kg. By comparison, the density of lead is 11340 kg/m3, and the densest element, Iridium, is 22650 kg/m3.
Toxicity
Generally, gold is non-toxic if consumed, and is used as food decoration in the form of gold leaf. However, consumption and thereby accumulation in body of large amount of gold (or gold compounds) is still toxic and the symptoms are similar to those of heavy metal poisoning.
Applications
As the metal
The 220kg Gold brick displayed in Chinkuashi Gold Museum, Taiwan.
Medium of monetary exchange. Pure gold is too soft for ordinary use and is typically hardened by alloying with silver, copper, or other metals. In various countries, gold, and its many alloys, are most often used in jewelry, coinage and as a standard for monetary exchange. The gold content of jewellery alloys is measured in carats (k), pure gold being designated as 24k. It is, however, more commonly sold in lower measurements of 22k, 18k, 14k and 10k. A lower "k" indicates a higher percent of silver, copper or other base metals in the alloy, copper being the more commonly used base metal. Fourteen carat gold-copper alloy is nearly identical in color to certain bronze alloys, and both may be used to produce police and other badges. Eighteen carat gold containing 25% copper is found in some antique jewelry and has a distinct, though not dominant, copper cast, creating an attractively warm color. When alloyed with silver alone, 18 carat gold appears yellow-green in color. White 18 carat gold can be made with 17.3% nickel, 5.5% zinc and 2.2% copper and is silver in appearance. Nickel is toxic, however, and its release from nickel white gold is controlled by legislation in Europe. Alternative white gold alloys are available based on palladium, silver and other white metals (World Gold Council), but the palladium alloys are more expensive than those using nickel. High-carat white gold alloys are far more resistant to corrosion than are either pure silver or sterling silver.
Gold coins intended for circulation from 1526 into the 1930s were typically a standard 22k alloy called crown gold, for hardness. Modern collector/investment bullion coins (which do not require good mechanical wear properties) are typically 24k, although the American Gold Eagle and British gold sovereign continue to be made at 22k, on historical tradition. Until recently, the Canadian Gold Maple Leaf coin contained the highest purity gold of any popular bullion coin, at 99.99% (.9999 fine). However, several other 99.99% pure gold coins are currently available, including Australia's Gold Kangaroos (first appearing in 1986 as the Australian Gold Nugget, with the kangaroo theme appearing in 1989), the several coins of the Australian Lunar Calendar series, and the Austrian Philharmonic. In 2006, the U.S. Mint began production of the American Buffalo gold bullion coin also at 99.99% purity.
Other uses:
In medieval times, gold was often seen as beneficial for the health, in the belief that something that rare and beautiful could not be anything but healthy. Even some modern esotericists and forms of alternative medicine assign metallic gold a healing power. Some gold salts do have anti-inflammatory properties and are used as pharmaceuticals in the treatment of arthritis and other similar conditions. However, only salts and radioisotopes of gold are of pharmacological value, as elemental (metallic) gold is inert to all chemicals it encounters inside the body.
Gold leaf, flake or dust is used on and in some gourmet foodstuffs, notably sweets and drinks as decorative ingredient.[2] Gold flake was used by the nobility in Medieval Europe as a decoration in foodstuffs and drinks, in the form of leafs, flakes or dust, either to demonstrate the host's wealth or in the honest belief that something that valuable and rare must be beneficial for one's health.
Gold solder is used for joining the components of gold jewellery by high-temperature hard soldering or brazing. If the work is to be of hallmarking quality, gold solder must match the carat weight of the work, and alloy formulae are manufactured in most industry-standard carat weights to colour match yellow and white gold. Gold solder is usually made in at least three melting-point ranges referred to as Easy, Medium and Hard. By using the hard, high-melting point solder first, followed by solders with progressively lower melting points, goldsmiths can assemble complex items with several separate soldered joints.
Goldwasser (German: "Goldwater") is a traditional herbal liqueur produced in Gdańsk, Poland and Schwabach, Germany and contains flakes of gold leaf. There are also some expensive (~$1000) cocktails which contain flakes of gold leaf. However, since metallic gold is inert to all body chemistry, it adds no taste nor has it any other nutritional effect and leaves the body unaltered.
Dentistry. Gold alloys are used in restorative dentistry, especially in tooth restorations, such as crowns and permanent bridges. The gold alloys' slight malleability facilitates the creation of a superior molar mating surface with other teeth and produces results that are generally more satisfactory than those produced by the creation of porcelain crowns. The use of gold crowns in more prominent teeth such as incisors is favored in some cultures and discouraged in others.
Gold can be made into thread and used in embroidery.
Gold is ductile and malleable, meaning it is able to be drawn into very thin wire and can be beaten into very thin sheets known as gold leaf.
Gold produces a deep, intense red color when used as a coloring agent in glass.
In photography, Gold toners are used to shift the colour of silver bromide black and white prints towards brown or blue tones, or to increase their stability. Used on sepia-toned prints, gold toners produce red tones. Kodak publish formulae for several types of gold toners, which use gold as the chloride (Kodak, 2006)
Electronics. The concentration of free electrons in gold metal is 5.90×1022 cm-3. Gold is highly conductive to electricity, and has been used for electrical wiring in some high energy applications (silver is even more conductive per volume, but gold has the advantage of corrosion resistance). For example, gold electrical wires were used during some of the Manhattan Project's atomic experiments, but large high current silver wires were used in the calutron isotope separator magnets in the project.
Though gold is attacked by free chlorine, its good conductivity and general resistance to oxidation and corrosion in other environments (including resistance to non-chlorinated acids) has led to its widespread industrial use in the electronic era as a thin layer coating electrical connectors of all kinds, thereby ensuring good connection. For example, gold is used in the connectors of the more expensive electronics cables, such as audio, video and USB cables. The benefit of using gold over other connector metals such as tin in these applications, is highly debated. Gold connectors are often criticized by audio-visual experts as unnecessary for most consumers and seen as simply a marketing ploy. However, the use of gold in other applications in electronic sliding contacts in highly humid or corrosive atmospheres, and in use for contacts with a very high failure cost (certain computers, communications equipment, spacecraft, jet aircraft engines) remains very common, and is unlikely to be replaced in the near future by any other metal.
Besides sliding electrical contacts, gold is also used in electrical contacts because of its resistance to corrosion, electrical conductivity, ductility and lack of toxicity.[3] Switch contacts are generally subjected to more intense corrosion stress than are sliding contacts.
Colloidal gold (Colloidal sols of gold nanoparticles) in water are intensely red - colored, and can be made with tightly-controlled particle sizes up to a few tens of nm across. Colloidal gold is used in research applications in medicine, biology and materials science. The technique of immunogold labeling exploits the ability of the gold particles to adsorb protein molecules onto their surfaces. Colloidal gold particles coated with specific antibodies can be used as probes for the presence and position of antigens on the surfaces of cells (Faulk and Taylor 1979). In ultrathin sections of tissues viewed by electron microscopy, the immunogold labels appear as extremely dense round spots at the position of the antigen (Roth et al. 1980). Colloidal gold is also the form of gold used as gold paint on ceramics prior to firing.
Gold, or alloys of gold and palladium, are applied as conductive coating to biological specimens and other non-conducting materials such as plastics and glass to be viewed in a scanning electron microscope. The coating, which is usually applied by sputtering with an argon plasma, has a triple role in this application. Gold's very high electrical conductivity drains electrical charge to earth, and its very high density provides stopping power for electrons in the SEM's electron beam, helping to limit the depth to which the electron beam penetrates the specimen. This improves definition of the position and topography of the specimen surface and increases the spatial resolution of the image. Gold also produces a high output of secondary electrons when irradiated by an electron beam, and these low-energy electrons are the most commonly-used signal source used in the scanning electron microscope.
Many competitions, and honors, such as the Olympics and the Nobel Prize, award a gold medal to the winner.
As gold is a good reflector of both infrared and visible light, it is used for the protective coatings on many artificial satellites and in infrared protective faceplates in thermal protection suits and astronauts' helmets.
White gold (an alloy of gold with platinum, palladium, nickel, and/or zinc) serves as a substitute for platinum.
Green gold (a gold/silver alloy) is used in specialized jewelry while gold alloys with copper are more standard, ranging from a pale yellow with little copper all the way to a deep pink with more copper (rose gold).
Blue gold can be made by alloying with iron
Purple gold can be made by alloying with aluminum (done rarely except in specialized jewelry)
Gold is used as the reflective layer on some high-end CDs.
The isotope gold-198, (half-life: 2.7 days) is used in some cancer treatments and for treating other diseases.[citation needed]
Gold can be used in food and has the E Number 175
As gold chemical compounds
Gold is attacked by and dissolves in alkaline solutions of potassium or sodium cyanide, and Gold cyanide is used commercially in electro-plating of gold onto base metals. Gold chloride (chloroauric acid) solutions are used to make colloidal gold by reduction with citrate or ascorbate ions. Gold chloride and gold oxide are used to make highly-valued cranberry or red-coloured glass, which like colloidal gold sols contains evenly-sized spherical gold nanoparticles.
History
Funerary mask of Tutankhamun
Gold has been known and highly valued since prehistoric times. It may have been the first metal used by humans and was valued for ornamentation and rituals. Egyptian hieroglyphs from as early as 2600 BC describe gold, which king Tushratta of the Mitanni claimed was "more plentiful than dirt" in Egypt.[4] Egypt and Nubia had the resources to make them major gold-producing areas for much of history. Gold is also mentioned several times in the Old Testament, and is included with the gifts of the magi in the first chapters of Matthew New Testament The south-east corner of the Black Sea was famed for its gold. Exploitation is said to date from the time of Midas, and this gold was important in the establishment of what is probably the world's earliest coinage in Lydia between 643 and 630 BC.
The European exploration of the Americas was fueled in no small part by reports of the gold ornaments displayed in great profusion by Native American peoples, especially in Central America, Peru, and Colombia.
Although the price of some platinum group metals can be much higher, gold has long been considered the most desirable of precious metals, and its value has been used as the standard for many currencies (known as the gold standard) in history. Gold has been used as a symbol for purity, value, royalty, and particularly roles that combine these properties. Gold as a sign of wealth and prestige was made fun of by Thomas More in his treatise Utopia. On that imaginary island, gold is so abundant that it is used to make chains for slaves, tableware and lavatory-seats. When ambassadors from other countries arrive, dressed in ostentatious gold jewels and badges, the Utopians mistake them for menial servants, paying homage instead to the most modestly-dressed of their party.
There is an age-old tradition of biting gold in order to test its authenticity. Although this is certainly not a professional way of examining gold, the bite test should score the gold because gold is considered a soft metal according to the Mohs' scale of mineral hardness. The purer the gold the easier it should be to mark it. Painted lead can cheat this test because lead is softer than gold (and may invite a small risk of lead poisoning if sufficient lead is absorbed by the biting).
This 156 ounce nugget was found by an individual prospector in the Southern California Desert using a metal detector.
Gold in antiquity was relatively easy to obtain geologically; however, 75% of all gold ever produced has been extracted since 1910.[5] It has been estimated that all the gold in the world that has ever been refined would form a single cube 20 m (66 ft) on a side (8000 m³).
The primary goal of the alchemists was to produce gold from other substances, such as lead — presumably by the interaction with a mythical substance called the philosopher's stone. Although they never succeeded in this attempt, the alchemists promoted an interest in what can be done with substances, and this laid a foundation for today's chemistry. Their symbol for gold was the circle with a point at its center (☉), which was also the astrological symbol, the Egyptian hieroglyph and the ancient Chinese character for the Sun (now 日). For modern attempts to produce artificial gold, see gold synthesis.
During the 19th century, gold rushes occurred whenever large gold deposits were discovered. The first major gold strike in the United States occurred in a small north Georgia town called Dahlonega.[6] Further gold rushes occurred in California, Colorado, Otago, Australia, Witwatersrand, Black Hills, and Klondike.
Because of its historically high value, much of the gold mined throughout history is still in circulation in one form or another.
Production
Main articles: Gold prospecting, Gold mining, and Gold extraction
The entrance to an underground gold mine in Victoria, Australia
Gold ore
Economic gold extraction can be achieved from ore grades as little as 0.5 g/1000 kg (0.5 ppm) on average in large easily mined deposits. Typical ore grades in open-pit mines are 1–5 g/1000 kg (1-5 ppm), ore grades in underground or hard rock mines are usually at least 3 g/1000 kg (3 ppm) on average. Since ore grades of 30 g/1000 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. Production in 1970 accounted for 79% of the world supply, producing about 1,000 tonnes. However, production in 2004 was 342 tonnes. This decline was due to the increasing difficulty of extraction and changing economic factors affecting the industry in South Africa.
The city of Johannesburg was built atop the world's greatest gold finds. Gold fields in the Free State and Gauteng provinces are deep and require the world's deepest mines. 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.
Gold nuggets From Arizona
Other major producers are Canada, United States and Australia. Mines in South Dakota and Nevada supply two-thirds of gold used in the United States. Siberian regions of Russia also used to be significant in the global gold mining industry. Kolar Gold Fields in India is another example of a city being built on the greatest gold deposits in India. 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.[7]
After initial production, gold is often subsequently refined industrially by the Wohlwill process or the Miller process. Other methods of assaying and purifying smaller amounts of gold include parting and inquartation as well as cuppelation, or refining methods based on the dissolution of gold in aqua regia.
The world's oceans hold a vast amount of gold, but in very low concentrations (perhaps 1-2 parts per billion). A number of people have claimed to be able to economically recover gold from sea water, but so far they have all been either mistaken or crooks. Reverend Prescott Jernegan ran a gold-from seawater swindle in America in the 1890s. A British fraud ran the same scam in England in the early 1900s.[8]
Fritz Haber (the German inventor of the Haber process) attempted commercial extraction of gold from sea water in an effort to help pay Germany's reparations following the First World War. Unfortunately, his assessment of the concentration of gold in sea water was unduly high, probably due to sample contamination. The effort produced little gold and cost the German government far more than the commercial value of the gold recovered. No commercially viable mechanism for performing gold extraction from sea water has yet been identified. Gold synthesis is not economically viable and is unlikely to become so in the foreseeable future.
The average gold mining and extraction costs are $238 per troy ounce but these can vary widely depending on mining type and ore quality. In 2001, global mine production amounted to 2,604 tonnes, or 67% of total gold demand in that year. At the end of 2001, it was estimated that all the gold ever mined totalled 145,000 tonnes.[9]
Price
Main articles: Gold as an investment and Gold standard
LBMA USD morning price fixings ($US per troy ounce) since 2001
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 karats being pure gold and lower ratings proportionally less. The purity of a gold bar 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 on the open market, but a procedure known as the Gold Fixing in London, originating in September 1919, provides a daily benchmark figure to the industry. The afternoon fixing appeared in 1968 to fix a price when US markets are open.
The high price of gold is due to its rare amount. Only three parts out of every billion (0.000000003) in the Earth's crust is gold.
Gold price per ounce in USD since 1968, in actual US$ and 2006 US$
Historically gold was used to back currency; in an economic 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 revalued 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.
On 17 March 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% of the gold ever mined, as does the similarly-laden U.S. Bullion Depository at Fort Knox.
Since 1968 the price of gold on the open market has ranged widely, with a record high of $850/oz ($27,300/kg) on 21 January 1980, to a low of $252.90/oz ($8,131/kg) on 21 June 1999 (London Fixing).[10] On 11 May 2006 the London gold fixing was $715.50/oz ($23,006/kg).[11]
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.[12]
Compounds
Although gold is a noble metal, it forms many and diverse compounds. The oxidation state of gold in its compound ranges from -1 to 5+ but Au(I) and Au(III) dominate. Gold(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 zig-zag polymeric chains, again featuring linear coordination at Au. Most drugs based on gold are Au(I) derivatives.[13]
Gold(III) (“auric”) is a common oxidation state and is illustrated by gold(III) chloride, AuCl3. Its derivative is chloroauric acid, HAuCl4, which forms when Au dissolves in aqua regia. Au(III) complexes, like other d8 compounds, are typically square planar.
Less common oxidation states: Au(-I), Au(II), and Au(V)
Compounds containing the Au- anion are called aurides. Caesium auride, CsAu which crystallizes in the caesium chloride motif. Other aurides include those of Rb+, K+, and tetramethylammonium (CH3)4N+.[14] Gold(II) compounds are usually diamagnetic with Au-Au bonds such as [Au(CH2)2P(C6H5)2]2Cl2. A noteworthy, legitimate Au(II) complex contains xenon as a ligand, [AuXe4](Sb2F11)2.[15] Gold pentafluoride is the sole example of Au(V), the highest verified oxidation state.[16]
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.[14] In such cases, gold has a fractional oxidation state. A representative example is the octahedral species {Au(P(C6H5)3)}62+. Gold chalcogenides, e.g. "AuS" feature equal amounts of Au(I) and Au(III).
Isotopes
There is one stable isotope of gold, and 18 radioisotopes with 195Au being the most stable with a half-life of 186 days.
Gold has been proposed as a "salting" material for nuclear weapons (cobalt is another, better-known salting material). A jacket of natural gold, irradiated by the intense high-energy neutron flux from an exploding thermonuclear weapon, would transmute into the radioactive isotope Au-198 with a half-life of 2.697 days and produce approximately .411 MeV of gamma radiation, significantly increasing the radioactivity of the weapon's fallout for several days. Such a weapon is not known to have ever been built, tested, or used.
Symbolism
Three Gold Sovereigns with a Krugerrand
Swiss-cast 1 kg gold bar.
Gold has been associated with the extremities of utmost evil and great sanctity throughout history. In the Book of Exodus, the Golden Calf is a symbol of idolatry and rebellion against God. In Communist propaganda, the golden pocket watch and its fastening golden chain were the characteristic accessories of the class enemy, the bourgeois and the industrial tycoons. Credit card companies associate their product with wealth by naming and colouring their top-of-the-range cards “gold;” although, in an attempt to out-do each other, platinum (and the even-more-elite black card) has now overtaken gold.
On the other hand 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. Eminent orators such as John Chrysostom were said to have a “mouth of gold with a silver tongue.” Gold is associated with notable anniversaries, particularly in a 50-year cycle, such as a golden wedding anniversary, golden jubilee, etc.
Great human achievements are frequently rewarded with gold, in the form of medals and decorations. Winners of races and prizes are usually awarded the gold medal (such as the Olympic Games and the Nobel Prize), while many award statues are depicted in gold (such as the Academy Awards, the Golden Globe Awards the Emmy Awards, the Palme d'Or, and the British Academy Film Awards).
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 are traditionally made of gold; since it is long-lasting and unaffected by the passage of time, it is considered a suitable material for everyday wear as well as a metaphor for the relationship. In Orthodox Christianity, the wedded couple is adorned with a golden crown during the ceremony, an amalgamation of symbolic rites.
The symbolic value of gold varies greatly around the world, even within geographic regions. For example, gold is quite common in Turkey but considered a most valuable gift in Sicily.
From most ancient times, gold has been connected to religion and spirituality, especially associated with the Sun. It was also seen as the best material to decorate religious imagery, all over history.
Gold forms the basis for a monetary standard used by the International Monetary Fund (IMF) and the Bank for International Settlements (BIS). Its ISO currency code is XAU. Modern industrial uses include dentistry and electronics, where gold has traditionally found use because of its good resistance to oxidative corrosion.
Chemically, gold is a trivalent and univalent transition metal. Gold does not react with most chemicals, but is attacked by chlorine, fluorine, aqua regia and cyanide. Gold dissolves in mercury, forming amalgam alloys. In particular, gold is insoluble in nitric acid, which will dissolve most other metals. Nitric acid has long been used to confirm the presence of gold in items, and this is the origin of the colloquial term "acid test," referring to a gold standard test for genuine value.
Contents[hide]
1 Characteristics
1.1 Toxicity
2 Applications
2.1 As the metal
2.2 As gold chemical compounds
3 History
4 Production
5 Price
6 Compounds
6.1 Less common oxidation states: Au(-I), Au(II), and Au(V)
6.2 Mixed valence compounds
7 Isotopes
8 Symbolism
9 References
10 See also
11 External links
//
Characteristics
Gold is the most malleable and ductile metal; a single gram can be beaten into a sheet of one square meter, or an ounce into 300 square feet. Gold readily forms alloys with many other metals. These alloys can be produced to increase the hardness or to create exotic colors. Adding copper yields a redder metal, iron blue, aluminium purple, platinum white, and natural bismuth and silver alloys produce black. Native gold contains usually eight to ten percent silver, but often much more — alloys with a silver content over 20% are called electrum. As the amount of silver increases, the color becomes whiter and the specific gravity becomes lower.
Gold is a good conductor of heat and electricity, and is not affected by air and most reagents. Heat, moisture, oxygen, and most corrosive agents have very little chemical effect on gold, making it well-suited for use in coins and jewelry; conversely, halogens will chemically alter gold, and aqua regia dissolves it by virtue of the elemental chlorine generated by this acid mixture.
Common oxidation states of gold include +1 (gold(I) or aurous compounds) and +3 (gold(III) or auric compounds). Gold ions in solution are readily reduced and precipitated out as gold metal by adding any other metal as the reducing agent. The added metal is oxidized and dissolves allowing the gold to be displaced from solution and be recovered as a solid precipitate.
Recent research undertaken by Sir Frank Reith of the Australian National University shows that microbes play an important role in forming gold deposits, transporting and precipitating gold to form grains and nuggets that collect in alluvial deposits.[1]
High quality pure metallic gold is tasteless, in keeping with its resistance to corrosion (it is metal ions which confer taste to metals).
In addition, gold is very dense, a cubic meter weighing 19300 kg. By comparison, the density of lead is 11340 kg/m3, and the densest element, Iridium, is 22650 kg/m3.
Toxicity
Generally, gold is non-toxic if consumed, and is used as food decoration in the form of gold leaf. However, consumption and thereby accumulation in body of large amount of gold (or gold compounds) is still toxic and the symptoms are similar to those of heavy metal poisoning.
Applications
As the metal
The 220kg Gold brick displayed in Chinkuashi Gold Museum, Taiwan.
Medium of monetary exchange. Pure gold is too soft for ordinary use and is typically hardened by alloying with silver, copper, or other metals. In various countries, gold, and its many alloys, are most often used in jewelry, coinage and as a standard for monetary exchange. The gold content of jewellery alloys is measured in carats (k), pure gold being designated as 24k. It is, however, more commonly sold in lower measurements of 22k, 18k, 14k and 10k. A lower "k" indicates a higher percent of silver, copper or other base metals in the alloy, copper being the more commonly used base metal. Fourteen carat gold-copper alloy is nearly identical in color to certain bronze alloys, and both may be used to produce police and other badges. Eighteen carat gold containing 25% copper is found in some antique jewelry and has a distinct, though not dominant, copper cast, creating an attractively warm color. When alloyed with silver alone, 18 carat gold appears yellow-green in color. White 18 carat gold can be made with 17.3% nickel, 5.5% zinc and 2.2% copper and is silver in appearance. Nickel is toxic, however, and its release from nickel white gold is controlled by legislation in Europe. Alternative white gold alloys are available based on palladium, silver and other white metals (World Gold Council), but the palladium alloys are more expensive than those using nickel. High-carat white gold alloys are far more resistant to corrosion than are either pure silver or sterling silver.
Gold coins intended for circulation from 1526 into the 1930s were typically a standard 22k alloy called crown gold, for hardness. Modern collector/investment bullion coins (which do not require good mechanical wear properties) are typically 24k, although the American Gold Eagle and British gold sovereign continue to be made at 22k, on historical tradition. Until recently, the Canadian Gold Maple Leaf coin contained the highest purity gold of any popular bullion coin, at 99.99% (.9999 fine). However, several other 99.99% pure gold coins are currently available, including Australia's Gold Kangaroos (first appearing in 1986 as the Australian Gold Nugget, with the kangaroo theme appearing in 1989), the several coins of the Australian Lunar Calendar series, and the Austrian Philharmonic. In 2006, the U.S. Mint began production of the American Buffalo gold bullion coin also at 99.99% purity.
Other uses:
In medieval times, gold was often seen as beneficial for the health, in the belief that something that rare and beautiful could not be anything but healthy. Even some modern esotericists and forms of alternative medicine assign metallic gold a healing power. Some gold salts do have anti-inflammatory properties and are used as pharmaceuticals in the treatment of arthritis and other similar conditions. However, only salts and radioisotopes of gold are of pharmacological value, as elemental (metallic) gold is inert to all chemicals it encounters inside the body.
Gold leaf, flake or dust is used on and in some gourmet foodstuffs, notably sweets and drinks as decorative ingredient.[2] Gold flake was used by the nobility in Medieval Europe as a decoration in foodstuffs and drinks, in the form of leafs, flakes or dust, either to demonstrate the host's wealth or in the honest belief that something that valuable and rare must be beneficial for one's health.
Gold solder is used for joining the components of gold jewellery by high-temperature hard soldering or brazing. If the work is to be of hallmarking quality, gold solder must match the carat weight of the work, and alloy formulae are manufactured in most industry-standard carat weights to colour match yellow and white gold. Gold solder is usually made in at least three melting-point ranges referred to as Easy, Medium and Hard. By using the hard, high-melting point solder first, followed by solders with progressively lower melting points, goldsmiths can assemble complex items with several separate soldered joints.
Goldwasser (German: "Goldwater") is a traditional herbal liqueur produced in Gdańsk, Poland and Schwabach, Germany and contains flakes of gold leaf. There are also some expensive (~$1000) cocktails which contain flakes of gold leaf. However, since metallic gold is inert to all body chemistry, it adds no taste nor has it any other nutritional effect and leaves the body unaltered.
Dentistry. Gold alloys are used in restorative dentistry, especially in tooth restorations, such as crowns and permanent bridges. The gold alloys' slight malleability facilitates the creation of a superior molar mating surface with other teeth and produces results that are generally more satisfactory than those produced by the creation of porcelain crowns. The use of gold crowns in more prominent teeth such as incisors is favored in some cultures and discouraged in others.
Gold can be made into thread and used in embroidery.
Gold is ductile and malleable, meaning it is able to be drawn into very thin wire and can be beaten into very thin sheets known as gold leaf.
Gold produces a deep, intense red color when used as a coloring agent in glass.
In photography, Gold toners are used to shift the colour of silver bromide black and white prints towards brown or blue tones, or to increase their stability. Used on sepia-toned prints, gold toners produce red tones. Kodak publish formulae for several types of gold toners, which use gold as the chloride (Kodak, 2006)
Electronics. The concentration of free electrons in gold metal is 5.90×1022 cm-3. Gold is highly conductive to electricity, and has been used for electrical wiring in some high energy applications (silver is even more conductive per volume, but gold has the advantage of corrosion resistance). For example, gold electrical wires were used during some of the Manhattan Project's atomic experiments, but large high current silver wires were used in the calutron isotope separator magnets in the project.
Though gold is attacked by free chlorine, its good conductivity and general resistance to oxidation and corrosion in other environments (including resistance to non-chlorinated acids) has led to its widespread industrial use in the electronic era as a thin layer coating electrical connectors of all kinds, thereby ensuring good connection. For example, gold is used in the connectors of the more expensive electronics cables, such as audio, video and USB cables. The benefit of using gold over other connector metals such as tin in these applications, is highly debated. Gold connectors are often criticized by audio-visual experts as unnecessary for most consumers and seen as simply a marketing ploy. However, the use of gold in other applications in electronic sliding contacts in highly humid or corrosive atmospheres, and in use for contacts with a very high failure cost (certain computers, communications equipment, spacecraft, jet aircraft engines) remains very common, and is unlikely to be replaced in the near future by any other metal.
Besides sliding electrical contacts, gold is also used in electrical contacts because of its resistance to corrosion, electrical conductivity, ductility and lack of toxicity.[3] Switch contacts are generally subjected to more intense corrosion stress than are sliding contacts.
Colloidal gold (Colloidal sols of gold nanoparticles) in water are intensely red - colored, and can be made with tightly-controlled particle sizes up to a few tens of nm across. Colloidal gold is used in research applications in medicine, biology and materials science. The technique of immunogold labeling exploits the ability of the gold particles to adsorb protein molecules onto their surfaces. Colloidal gold particles coated with specific antibodies can be used as probes for the presence and position of antigens on the surfaces of cells (Faulk and Taylor 1979). In ultrathin sections of tissues viewed by electron microscopy, the immunogold labels appear as extremely dense round spots at the position of the antigen (Roth et al. 1980). Colloidal gold is also the form of gold used as gold paint on ceramics prior to firing.
Gold, or alloys of gold and palladium, are applied as conductive coating to biological specimens and other non-conducting materials such as plastics and glass to be viewed in a scanning electron microscope. The coating, which is usually applied by sputtering with an argon plasma, has a triple role in this application. Gold's very high electrical conductivity drains electrical charge to earth, and its very high density provides stopping power for electrons in the SEM's electron beam, helping to limit the depth to which the electron beam penetrates the specimen. This improves definition of the position and topography of the specimen surface and increases the spatial resolution of the image. Gold also produces a high output of secondary electrons when irradiated by an electron beam, and these low-energy electrons are the most commonly-used signal source used in the scanning electron microscope.
Many competitions, and honors, such as the Olympics and the Nobel Prize, award a gold medal to the winner.
As gold is a good reflector of both infrared and visible light, it is used for the protective coatings on many artificial satellites and in infrared protective faceplates in thermal protection suits and astronauts' helmets.
White gold (an alloy of gold with platinum, palladium, nickel, and/or zinc) serves as a substitute for platinum.
Green gold (a gold/silver alloy) is used in specialized jewelry while gold alloys with copper are more standard, ranging from a pale yellow with little copper all the way to a deep pink with more copper (rose gold).
Blue gold can be made by alloying with iron
Purple gold can be made by alloying with aluminum (done rarely except in specialized jewelry)
Gold is used as the reflective layer on some high-end CDs.
The isotope gold-198, (half-life: 2.7 days) is used in some cancer treatments and for treating other diseases.[citation needed]
Gold can be used in food and has the E Number 175
As gold chemical compounds
Gold is attacked by and dissolves in alkaline solutions of potassium or sodium cyanide, and Gold cyanide is used commercially in electro-plating of gold onto base metals. Gold chloride (chloroauric acid) solutions are used to make colloidal gold by reduction with citrate or ascorbate ions. Gold chloride and gold oxide are used to make highly-valued cranberry or red-coloured glass, which like colloidal gold sols contains evenly-sized spherical gold nanoparticles.
History
Funerary mask of Tutankhamun
Gold has been known and highly valued since prehistoric times. It may have been the first metal used by humans and was valued for ornamentation and rituals. Egyptian hieroglyphs from as early as 2600 BC describe gold, which king Tushratta of the Mitanni claimed was "more plentiful than dirt" in Egypt.[4] Egypt and Nubia had the resources to make them major gold-producing areas for much of history. Gold is also mentioned several times in the Old Testament, and is included with the gifts of the magi in the first chapters of Matthew New Testament The south-east corner of the Black Sea was famed for its gold. Exploitation is said to date from the time of Midas, and this gold was important in the establishment of what is probably the world's earliest coinage in Lydia between 643 and 630 BC.
The European exploration of the Americas was fueled in no small part by reports of the gold ornaments displayed in great profusion by Native American peoples, especially in Central America, Peru, and Colombia.
Although the price of some platinum group metals can be much higher, gold has long been considered the most desirable of precious metals, and its value has been used as the standard for many currencies (known as the gold standard) in history. Gold has been used as a symbol for purity, value, royalty, and particularly roles that combine these properties. Gold as a sign of wealth and prestige was made fun of by Thomas More in his treatise Utopia. On that imaginary island, gold is so abundant that it is used to make chains for slaves, tableware and lavatory-seats. When ambassadors from other countries arrive, dressed in ostentatious gold jewels and badges, the Utopians mistake them for menial servants, paying homage instead to the most modestly-dressed of their party.
There is an age-old tradition of biting gold in order to test its authenticity. Although this is certainly not a professional way of examining gold, the bite test should score the gold because gold is considered a soft metal according to the Mohs' scale of mineral hardness. The purer the gold the easier it should be to mark it. Painted lead can cheat this test because lead is softer than gold (and may invite a small risk of lead poisoning if sufficient lead is absorbed by the biting).
This 156 ounce nugget was found by an individual prospector in the Southern California Desert using a metal detector.
Gold in antiquity was relatively easy to obtain geologically; however, 75% of all gold ever produced has been extracted since 1910.[5] It has been estimated that all the gold in the world that has ever been refined would form a single cube 20 m (66 ft) on a side (8000 m³).
The primary goal of the alchemists was to produce gold from other substances, such as lead — presumably by the interaction with a mythical substance called the philosopher's stone. Although they never succeeded in this attempt, the alchemists promoted an interest in what can be done with substances, and this laid a foundation for today's chemistry. Their symbol for gold was the circle with a point at its center (☉), which was also the astrological symbol, the Egyptian hieroglyph and the ancient Chinese character for the Sun (now 日). For modern attempts to produce artificial gold, see gold synthesis.
During the 19th century, gold rushes occurred whenever large gold deposits were discovered. The first major gold strike in the United States occurred in a small north Georgia town called Dahlonega.[6] Further gold rushes occurred in California, Colorado, Otago, Australia, Witwatersrand, Black Hills, and Klondike.
Because of its historically high value, much of the gold mined throughout history is still in circulation in one form or another.
Production
Main articles: Gold prospecting, Gold mining, and Gold extraction
The entrance to an underground gold mine in Victoria, Australia
Gold ore
Economic gold extraction can be achieved from ore grades as little as 0.5 g/1000 kg (0.5 ppm) on average in large easily mined deposits. Typical ore grades in open-pit mines are 1–5 g/1000 kg (1-5 ppm), ore grades in underground or hard rock mines are usually at least 3 g/1000 kg (3 ppm) on average. Since ore grades of 30 g/1000 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. Production in 1970 accounted for 79% of the world supply, producing about 1,000 tonnes. However, production in 2004 was 342 tonnes. This decline was due to the increasing difficulty of extraction and changing economic factors affecting the industry in South Africa.
The city of Johannesburg was built atop the world's greatest gold finds. Gold fields in the Free State and Gauteng provinces are deep and require the world's deepest mines. 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.
Gold nuggets From Arizona
Other major producers are Canada, United States and Australia. Mines in South Dakota and Nevada supply two-thirds of gold used in the United States. Siberian regions of Russia also used to be significant in the global gold mining industry. Kolar Gold Fields in India is another example of a city being built on the greatest gold deposits in India. 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.[7]
After initial production, gold is often subsequently refined industrially by the Wohlwill process or the Miller process. Other methods of assaying and purifying smaller amounts of gold include parting and inquartation as well as cuppelation, or refining methods based on the dissolution of gold in aqua regia.
The world's oceans hold a vast amount of gold, but in very low concentrations (perhaps 1-2 parts per billion). A number of people have claimed to be able to economically recover gold from sea water, but so far they have all been either mistaken or crooks. Reverend Prescott Jernegan ran a gold-from seawater swindle in America in the 1890s. A British fraud ran the same scam in England in the early 1900s.[8]
Fritz Haber (the German inventor of the Haber process) attempted commercial extraction of gold from sea water in an effort to help pay Germany's reparations following the First World War. Unfortunately, his assessment of the concentration of gold in sea water was unduly high, probably due to sample contamination. The effort produced little gold and cost the German government far more than the commercial value of the gold recovered. No commercially viable mechanism for performing gold extraction from sea water has yet been identified. Gold synthesis is not economically viable and is unlikely to become so in the foreseeable future.
The average gold mining and extraction costs are $238 per troy ounce but these can vary widely depending on mining type and ore quality. In 2001, global mine production amounted to 2,604 tonnes, or 67% of total gold demand in that year. At the end of 2001, it was estimated that all the gold ever mined totalled 145,000 tonnes.[9]
Price
Main articles: Gold as an investment and Gold standard
LBMA USD morning price fixings ($US per troy ounce) since 2001
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 karats being pure gold and lower ratings proportionally less. The purity of a gold bar 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 on the open market, but a procedure known as the Gold Fixing in London, originating in September 1919, provides a daily benchmark figure to the industry. The afternoon fixing appeared in 1968 to fix a price when US markets are open.
The high price of gold is due to its rare amount. Only three parts out of every billion (0.000000003) in the Earth's crust is gold.
Gold price per ounce in USD since 1968, in actual US$ and 2006 US$
Historically gold was used to back currency; in an economic 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 revalued 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.
On 17 March 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% of the gold ever mined, as does the similarly-laden U.S. Bullion Depository at Fort Knox.
Since 1968 the price of gold on the open market has ranged widely, with a record high of $850/oz ($27,300/kg) on 21 January 1980, to a low of $252.90/oz ($8,131/kg) on 21 June 1999 (London Fixing).[10] On 11 May 2006 the London gold fixing was $715.50/oz ($23,006/kg).[11]
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.[12]
Compounds
Although gold is a noble metal, it forms many and diverse compounds. The oxidation state of gold in its compound ranges from -1 to 5+ but Au(I) and Au(III) dominate. Gold(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 zig-zag polymeric chains, again featuring linear coordination at Au. Most drugs based on gold are Au(I) derivatives.[13]
Gold(III) (“auric”) is a common oxidation state and is illustrated by gold(III) chloride, AuCl3. Its derivative is chloroauric acid, HAuCl4, which forms when Au dissolves in aqua regia. Au(III) complexes, like other d8 compounds, are typically square planar.
Less common oxidation states: Au(-I), Au(II), and Au(V)
Compounds containing the Au- anion are called aurides. Caesium auride, CsAu which crystallizes in the caesium chloride motif. Other aurides include those of Rb+, K+, and tetramethylammonium (CH3)4N+.[14] Gold(II) compounds are usually diamagnetic with Au-Au bonds such as [Au(CH2)2P(C6H5)2]2Cl2. A noteworthy, legitimate Au(II) complex contains xenon as a ligand, [AuXe4](Sb2F11)2.[15] Gold pentafluoride is the sole example of Au(V), the highest verified oxidation state.[16]
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.[14] In such cases, gold has a fractional oxidation state. A representative example is the octahedral species {Au(P(C6H5)3)}62+. Gold chalcogenides, e.g. "AuS" feature equal amounts of Au(I) and Au(III).
Isotopes
There is one stable isotope of gold, and 18 radioisotopes with 195Au being the most stable with a half-life of 186 days.
Gold has been proposed as a "salting" material for nuclear weapons (cobalt is another, better-known salting material). A jacket of natural gold, irradiated by the intense high-energy neutron flux from an exploding thermonuclear weapon, would transmute into the radioactive isotope Au-198 with a half-life of 2.697 days and produce approximately .411 MeV of gamma radiation, significantly increasing the radioactivity of the weapon's fallout for several days. Such a weapon is not known to have ever been built, tested, or used.
Symbolism
Three Gold Sovereigns with a Krugerrand
Swiss-cast 1 kg gold bar.
Gold has been associated with the extremities of utmost evil and great sanctity throughout history. In the Book of Exodus, the Golden Calf is a symbol of idolatry and rebellion against God. In Communist propaganda, the golden pocket watch and its fastening golden chain were the characteristic accessories of the class enemy, the bourgeois and the industrial tycoons. Credit card companies associate their product with wealth by naming and colouring their top-of-the-range cards “gold;” although, in an attempt to out-do each other, platinum (and the even-more-elite black card) has now overtaken gold.
On the other hand 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. Eminent orators such as John Chrysostom were said to have a “mouth of gold with a silver tongue.” Gold is associated with notable anniversaries, particularly in a 50-year cycle, such as a golden wedding anniversary, golden jubilee, etc.
Great human achievements are frequently rewarded with gold, in the form of medals and decorations. Winners of races and prizes are usually awarded the gold medal (such as the Olympic Games and the Nobel Prize), while many award statues are depicted in gold (such as the Academy Awards, the Golden Globe Awards the Emmy Awards, the Palme d'Or, and the British Academy Film Awards).
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 are traditionally made of gold; since it is long-lasting and unaffected by the passage of time, it is considered a suitable material for everyday wear as well as a metaphor for the relationship. In Orthodox Christianity, the wedded couple is adorned with a golden crown during the ceremony, an amalgamation of symbolic rites.
The symbolic value of gold varies greatly around the world, even within geographic regions. For example, gold is quite common in Turkey but considered a most valuable gift in Sicily.
From most ancient times, gold has been connected to religion and spirituality, especially associated with the Sun. It was also seen as the best material to decorate religious imagery, all over history.
วันพุธที่ ๙ พฤษภาคม พ.ศ. ๒๕๕๐
Fine and Fake Jewellery
Gold in Egypt 3000 BC
In the ancient world gold was the preferred metal for making jewellery. It was rare, did not tarnish and best of all it was malleable, so it could be worked fairly easily.
Magnificent bracelets, pendants, necklaces, rings, armlets, earrings, diadems, head ornaments, pectoral ornaments and collars of gold were all produced in ancient Egypt, the land of the Pharaohs.
Excavations by Howard Carter in 1922 led to the great discovery of Tutankhamun's tomb and many gold funerary artefacts, all showing the art work of ancient Egypt.
Left - Gold funeral mask of King Tutankhamun.
Gold and Gems in Greece 1400 BC
In ancient Greece, beads shaped as natural forms like shells, flowers and beetles were manufactured on a large scale. Beautiful and delicate necklaces and earrings were found in burial sites in Northern Greece. By 300 BC the Greeks were making multi coloured jewellery and used emeralds, garnets, amethysts and pearls. Right - Greek earrings.
They also used coloured stones, glass and enamel. Carved cameos of Indian Sardonyx (a striped brown pink and cream agate stone) along with filigree gold work were widely made. Beads were made by joining two flat pieces of gold and filling them with sand.
Italian Gold and Roman Coinage
Eight centuries BC the Italian Etruscans in the Tuscany region produced granulated textured gold work. They made large fibulae or clasps, necklaces, bracelets and earrings. They also made pendants that were hollow and could be filled with perfume. The Italians are still renowned for high quality stylish trend making gold work today.
In coinage the Romans used 18 and 24 carat gold. Being fairly easily available the coinage was the craftsman's raw material for decorative jewel work. 2000 years ago the Romans were using sapphires from Sri Lanka, cloudy emeralds, garnets, amber and Indian diamond crystals. When England was under Roman rule, fossilized wood called jet from the North of England was carved into interesting pieces.
C13th Medieval Sumptuary Laws
Sumptuary Laws in C13th Medieval Europe came into force and capped luxury in dress and jewellery. Townspeople in France, were not allowed to wear girdles or coronals made of pearls, gemstones, gold or silver. Similar laws existed in England. The fact that these laws forbade yeomen and artisans from wearing gold and silver indicates how the status of jewellery and sumptuous dress had become widespread beyond just the nobility.
Gems and Pearls Real and Fake
Jewels have always been used as love tokens and whilst many pieces were fine gems and precious metals, good fake jewellery intended to deceive existed. True gemstones and pearls originated from the east and were bought chiefly by the Italians. The Italian merchants then sold the goods on in Europe. Good glass imitations were often used and sometimes with intent as in royal funerary robes and children's jewellery.
Flawless, round, natural, large white pearls were prized more than precious gemstones. The finest of pearls were provided by South India and the Persian Gulf. The Italians, particularly the Venetians and people from Murano, could make imitation glass gems and pearls that were very good likenesses of the real jewels. Recipes for false pearls existed in 1300 when white powdered glass mixed with albumen (egg white) and snail slime, produced beads that were used as imitation pearls.
The Importance of C17th Earrings and Dress Ornaments
In the C17th a woman always donned her earrings whether dressed or undressed. By day fake pearl earrings and paste earrings to coordinate with clothing were acceptable. Fine diamond jewellery was kept for evening and embroidered stomachers which formed part of the dress frontage, could be decorated by jewels.
Suites of left and right coordinating jewelled pieces called dress ornaments decreased in size as they were placed down the stomacher. Sometimes the sleeves or skirts were decorated with smaller matching brooches.
Dress ornaments in the form of diamond bows and shuttles. As many as 42 shuttles could be used to decorate a dress.
17th Century Fake Pearls and Strass Paste Gems
In the 1630s large quantities of pearls were used as clothing accessories. To be truly fashionable pearls needed to be worn in abundance. In the C17th, Jaquin of Paris patented a method of making fake pearls. He coated blown glass hollow balls with varnish mixed with iridescent ground fish scales. The hollow balls were then filled with wax to strengthen them. This method made Paris the main producer of fake pearls for over 200 years.
Paste is a compound of glass containing white lead oxide and potash. Paste jewellery was usual in the 1670s and was worn at court. The best and most long lasting paste jewellery was produced after 1734 by Georges Strass. Most fake jewellery was Paris led. Just about any kind of fake gem could be made, including fake opals. Many pieces of fake jewellery have survived in their original setting, but fine estate pieces of real gems were often broken up for resetting into more fashionable styles of the era.
After 1760 the production of fake jewellery spread to London and to Birmingham. Steel which was produced easily during the industrial revolution was used for settings for marcasite and jasper ware cameos. Glass and Wedgwood porcelain paste cameos were made in English factories and were very popular too.
Ornate shoe buckles of paste, steel and tin were part of fashionable dress. A similar fad at this time were elaborate paste jewelled buttons, fashionable in British society. As well as fake jewellery gaining popularity, semi precious jewels such as uncut garnets became usual as part of less formal day dress.
Empire Jewellery
When Napoleon eventually emerged as Emperor of France in 1804 he revived jewellery and fashion as a new court of pomp and ostentatious display evolved.
'Joailliers' worked fine jewellery and 'bijoutiers' used less precious materials.
The members of the new French imperial family had the former French royal family gems re-set in the latest neo-classical style. These new trends in jewellery were copied in Europe and particularly England. Greek and Roman architecture were the main influence for designs as famous discoveries of ancient treasure had not yet happened.
Parures
Parures were a matching suite of coordinating precious gems which could include a necklace, a comb, a tiara, a diadem, a bandeau, a pair of bracelets, pins, rings, drop earrings or and cluster stud earrings and possibly a belt clasp. Both Josephine and later Napoleon's second wife had magnificent sets of Parures.
Right - Parure consisting of bracelet, necklace, ring and earrings.
TO TOP OF PAGE
Cameos
After Napoleon's cameo decorated coronation crown was seen, cameos were the rage.
Sometimes cameos were carved from hardstone, but more often from substitutes like conch shells and set pieces of Wedgwood porcelain.
Left - Carved cameo scene.
Victorian Jewellery
When Queen Victoria came to the throne in 1837 jewellery was romantic and nationalistic. It gave attention to the pressure of European folk art, which later influenced the Arts and Crafts Movement. Until mid century most western jewellery came from Europe, but soon jewellery began to be made in America and Australia.
Although jewellery had been made by multiple methods of production for centuries, mid Victorian mass production in Birmingham (England), Germany and Providence, Rhode Island meant that standards were lowered.
Victorian women rebelled when they saw some of the machine made jewellery on offer, although much of what has survived is of good quality. Many wore no jewellery at all, or bought from the artist craftsman jewellers who emerged at much the same time.
Some jewellers like Tiffany began to make fine jewellery of such high standard that they soon opened shops in main cities of Europe.
Right - Victorian garnet necklace.
Mourning Jewellery
There was a huge fashion for mourning jewellery which highlights how sentimental the Victorian age was. The initial months of mourning were unadorned by jewellery of any kind. As the mourning rituals increased, mourning jewellery developed as a fashion item. Jet jewellery was worn a great deal by Queen Victoria after Prince Albert's death.
Jet from Whitby, North of England was set into mourning pieces. All types of material that were black were used and almost all included a lock of the dead loved one's hair. Hair was also plaited, braided or twisted very tightly until it became hard and thread like. To many of us living in the twenty first century the use of hair is an unattractive side of some antique jewellery.
Arts and Crafts Jewellery
The new design philosophy of Arts and Crafts that sprang up after 1870 was a reaction to mass produced goods and inferior machine made products. It was a reaction to the shoddy interior and ornamental products of the industrial revolution. Leaders of the movement in England included William Morris and John Ruskin and they promoted simple Arts and Crafts of designs based on floral, primitive or Celtic forms worked as wallpapers, furniture and jewellery.
The polished stones used in Arts and Crafts jewellery gave a medieval, simpler, gentler, tooled hand made look and feel to items. People inspired by the movement to produce work of a more individual nature included Liberty of London and Renee Mackintosh of Glasgow. By 1900, Arts and Crafts as a movement declined, so Art Nouveau, a more ostentatious version started in France took root.
Art Nouveau
Art Nouveau jewellery follows curving sinuous organic lines of romantic and imaginary dreaminess, with long limbed ethereal beauties sometimes turning into winged bird and flower forms. The movement began in Paris and its influence went throughout the Western world.
The Frenchman René Lalique was the master goldsmith of the era of Art Nouveau producing exquisite one off pieces. As an art movement today, the style is still admired and still copied.
Magnificent floral and botanical forms often worked in enamel were inexpensive and became so popular once mass-produced, that the Art Nouveau style declined.
Queen Alexandra's Pearls
Most fine jewellery in the 1900s was white and made from either diamonds or pearls. Queen Alexandra initially wore dog collar chokers, called a 'collier de chien' to cover a small scar on her neck.
Left - Queen Alexandra who wore pearls from neck to waist.
For state occasions and formal events she plastered herself in arrangements of pearl necklaces. The rarity value of real pearls then was such that an American skyscraper exchanged hands for the price of a pearl necklace.
This is not so ridiculous as it seems, as fine south sea pearls still command a high price.
TO TOP OF PAGE
Mikimoto Pearls
Pearls were very fashionable, but still very, very costly. After the 1890s Kokichi Mikimoto of Japan produced highly acceptable cultured pearls by placing a small bead into an oyster shell. The bead coated itself with nacre (mother of pearl) and so good looking pearl jewels became more affordable.
When I see Mikimoto pearls today I always think their lustre far surpasses any other pearl made this way.
Pearls
Various combinations of pearl necklaces come in and out of fashion with regularity so pearls too are a must. Both fake and real freshwater or cultured pearls are very affordable today. Many are now bought from China since trade opened up in the nineties. The price of pearls has dropped by about a fifth in the past 10 years and the Chinese are making waves in the pearl world with their cheaper prices. The Japanese have suffered disease in their pearl beds as well as facing competition and are finding it hard to compete with China's prices.
Pearl necklaces and pearl earrings can lift a complexion and bring light and radiance to the face taking years off a woman whatever her age. If you can afford it, invest in a pair of Mabe pearl earrings. They have a wonderful white glow with a size about one centimetre across and look expensive. Expect to pay about £300 for a pair trimmed with 9ct gold. Look after them by rubbing gently with a pure silk scarf, store in their original box and always put them on after applying perfume and hair products. A matching real pearl necklace freshwater or cultured, will enhance them and you.
Pearls are currently back in fashion again and with the modern twist of being interspaced on gold wire or floating on special synthetic cord they are essential to the millennium look. Look out for variations too on drop pearl earrings in the next year or so. PP
Cocktail Jewellery
In the 1920s Lalique designed good mass produced quality glass jewellery. Fake, or costume jewellery was sometimes then called cocktail jewellery. It was greatly influenced by Coco Chanel (1883-1971) and Elsa Schiaparelli (1890-1973). They both encouraged clients to use costume jewellery and to mix it with genuine gem pieces they already owned. Both designers offered imagination and fun and both often sported fabulous fakes.
In the late 1930s Napier of the USA was at the forefront of manufacturing fake cocktail jewels, which offered glamour and escapism. Napier still produces excellent contemporary costume pieces.
Hollywood Influence
By the 1940s and 1950s American culture was very dominant in Europe. The influence of movie films and the prominence of film stars set the fashion in manners, make-up, hair and clothes. People wanted look alike copies of outfits and jewellery worn by screen idols. It was widely believed that Hollywood glamour would rub off on you if you had the clothes and developed the look.
The Second World War in Europe halted production of fine jewellery when metals were rationed. New estate type, fine precious metal and gem jewellery was simply not available. Quality costume jewellery which was flourishing in America, became much more acceptable and was a real alternative to fine jewellery.
Because of technical advances in production methods, a huge range of styles was available from America, and since it was so popular the market became dynamic and inventive and affordable.
1980's Television Influence - Dynasty, Dallas and Diamante
In the 1980s there was a huge revival of costume jewellery after the glitzy scenes from the television soap operas Dynasty and Dallas were watched by 250 million viewers in the consumer boon of the 1980s. Diamante by day became the norm in reality and earrings reached such huge proportions that the 1990s saw a reaction which quickly dated lavish dress jewellery as the fashion for tiny real diamond studs or a fine stud pearls became the only earring to wear. As soon as the fashion was declared dead by everyone, including grandmothers, it was revived again in 2000AD by the fashion cognoscenti. Now fabulous fakes, especially brooches have gained ground once more.
Jewellery for the 21st Century
Costume jewellery can enliven a fashion wardrobe and bring a dash of panache especially for one off special occasions. Costume jewellery can be superb. The superb is usually plated at least seven times with 18 or 22 ct gold.
For example Joan Rivers does a range of good costume jewellery modelled on original fine gem pieces. One of her trademarks is to make jewellery doubly useful and she produces sets of interchangeable earrings, pendants and tennis bracelets. For example you might be able to slip a range of up to 10 different coloured stones, pearls or Swarovski crystals into an 18ct gold plated earring to vary the look. Her jewellery is exclusive to the QVC shopping channel in the UK and she is constantly working on new ideas such is her enthusiasm.
Highest grade Cubic Zirconium man made imitation diamonds often set in precious metals is of such a good standard that almost everyone can afford to have attractive jewellery.
The best crystals used in costume jewellery are the first grade crystals that the top Austrian firm Swarovski can offer. Butler and Wilson costume brooch.
Some of the costume jewellery I have come to love, comes from companies like Ciro, Adrian Buckley, Butler and Wilson, Swarovski Crystal Jewelry Napier, Joan Rivers, Joan Collins, Christian Dior, California Crystal, Property of A Lady and of course Kenneth J Lane.
In the ancient world gold was the preferred metal for making jewellery. It was rare, did not tarnish and best of all it was malleable, so it could be worked fairly easily.
Magnificent bracelets, pendants, necklaces, rings, armlets, earrings, diadems, head ornaments, pectoral ornaments and collars of gold were all produced in ancient Egypt, the land of the Pharaohs.
Excavations by Howard Carter in 1922 led to the great discovery of Tutankhamun's tomb and many gold funerary artefacts, all showing the art work of ancient Egypt.
Left - Gold funeral mask of King Tutankhamun.
Gold and Gems in Greece 1400 BC
In ancient Greece, beads shaped as natural forms like shells, flowers and beetles were manufactured on a large scale. Beautiful and delicate necklaces and earrings were found in burial sites in Northern Greece. By 300 BC the Greeks were making multi coloured jewellery and used emeralds, garnets, amethysts and pearls. Right - Greek earrings.
They also used coloured stones, glass and enamel. Carved cameos of Indian Sardonyx (a striped brown pink and cream agate stone) along with filigree gold work were widely made. Beads were made by joining two flat pieces of gold and filling them with sand.
Italian Gold and Roman Coinage
Eight centuries BC the Italian Etruscans in the Tuscany region produced granulated textured gold work. They made large fibulae or clasps, necklaces, bracelets and earrings. They also made pendants that were hollow and could be filled with perfume. The Italians are still renowned for high quality stylish trend making gold work today.
In coinage the Romans used 18 and 24 carat gold. Being fairly easily available the coinage was the craftsman's raw material for decorative jewel work. 2000 years ago the Romans were using sapphires from Sri Lanka, cloudy emeralds, garnets, amber and Indian diamond crystals. When England was under Roman rule, fossilized wood called jet from the North of England was carved into interesting pieces.
C13th Medieval Sumptuary Laws
Sumptuary Laws in C13th Medieval Europe came into force and capped luxury in dress and jewellery. Townspeople in France, were not allowed to wear girdles or coronals made of pearls, gemstones, gold or silver. Similar laws existed in England. The fact that these laws forbade yeomen and artisans from wearing gold and silver indicates how the status of jewellery and sumptuous dress had become widespread beyond just the nobility.
Gems and Pearls Real and Fake
Jewels have always been used as love tokens and whilst many pieces were fine gems and precious metals, good fake jewellery intended to deceive existed. True gemstones and pearls originated from the east and were bought chiefly by the Italians. The Italian merchants then sold the goods on in Europe. Good glass imitations were often used and sometimes with intent as in royal funerary robes and children's jewellery.
Flawless, round, natural, large white pearls were prized more than precious gemstones. The finest of pearls were provided by South India and the Persian Gulf. The Italians, particularly the Venetians and people from Murano, could make imitation glass gems and pearls that were very good likenesses of the real jewels. Recipes for false pearls existed in 1300 when white powdered glass mixed with albumen (egg white) and snail slime, produced beads that were used as imitation pearls.
The Importance of C17th Earrings and Dress Ornaments
In the C17th a woman always donned her earrings whether dressed or undressed. By day fake pearl earrings and paste earrings to coordinate with clothing were acceptable. Fine diamond jewellery was kept for evening and embroidered stomachers which formed part of the dress frontage, could be decorated by jewels.
Suites of left and right coordinating jewelled pieces called dress ornaments decreased in size as they were placed down the stomacher. Sometimes the sleeves or skirts were decorated with smaller matching brooches.
Dress ornaments in the form of diamond bows and shuttles. As many as 42 shuttles could be used to decorate a dress.
17th Century Fake Pearls and Strass Paste Gems
In the 1630s large quantities of pearls were used as clothing accessories. To be truly fashionable pearls needed to be worn in abundance. In the C17th, Jaquin of Paris patented a method of making fake pearls. He coated blown glass hollow balls with varnish mixed with iridescent ground fish scales. The hollow balls were then filled with wax to strengthen them. This method made Paris the main producer of fake pearls for over 200 years.
Paste is a compound of glass containing white lead oxide and potash. Paste jewellery was usual in the 1670s and was worn at court. The best and most long lasting paste jewellery was produced after 1734 by Georges Strass. Most fake jewellery was Paris led. Just about any kind of fake gem could be made, including fake opals. Many pieces of fake jewellery have survived in their original setting, but fine estate pieces of real gems were often broken up for resetting into more fashionable styles of the era.
After 1760 the production of fake jewellery spread to London and to Birmingham. Steel which was produced easily during the industrial revolution was used for settings for marcasite and jasper ware cameos. Glass and Wedgwood porcelain paste cameos were made in English factories and were very popular too.
Ornate shoe buckles of paste, steel and tin were part of fashionable dress. A similar fad at this time were elaborate paste jewelled buttons, fashionable in British society. As well as fake jewellery gaining popularity, semi precious jewels such as uncut garnets became usual as part of less formal day dress.
Empire Jewellery
When Napoleon eventually emerged as Emperor of France in 1804 he revived jewellery and fashion as a new court of pomp and ostentatious display evolved.
'Joailliers' worked fine jewellery and 'bijoutiers' used less precious materials.
The members of the new French imperial family had the former French royal family gems re-set in the latest neo-classical style. These new trends in jewellery were copied in Europe and particularly England. Greek and Roman architecture were the main influence for designs as famous discoveries of ancient treasure had not yet happened.
Parures
Parures were a matching suite of coordinating precious gems which could include a necklace, a comb, a tiara, a diadem, a bandeau, a pair of bracelets, pins, rings, drop earrings or and cluster stud earrings and possibly a belt clasp. Both Josephine and later Napoleon's second wife had magnificent sets of Parures.
Right - Parure consisting of bracelet, necklace, ring and earrings.
TO TOP OF PAGE
Cameos
After Napoleon's cameo decorated coronation crown was seen, cameos were the rage.
Sometimes cameos were carved from hardstone, but more often from substitutes like conch shells and set pieces of Wedgwood porcelain.
Left - Carved cameo scene.
Victorian Jewellery
When Queen Victoria came to the throne in 1837 jewellery was romantic and nationalistic. It gave attention to the pressure of European folk art, which later influenced the Arts and Crafts Movement. Until mid century most western jewellery came from Europe, but soon jewellery began to be made in America and Australia.
Although jewellery had been made by multiple methods of production for centuries, mid Victorian mass production in Birmingham (England), Germany and Providence, Rhode Island meant that standards were lowered.
Victorian women rebelled when they saw some of the machine made jewellery on offer, although much of what has survived is of good quality. Many wore no jewellery at all, or bought from the artist craftsman jewellers who emerged at much the same time.
Some jewellers like Tiffany began to make fine jewellery of such high standard that they soon opened shops in main cities of Europe.
Right - Victorian garnet necklace.
Mourning Jewellery
There was a huge fashion for mourning jewellery which highlights how sentimental the Victorian age was. The initial months of mourning were unadorned by jewellery of any kind. As the mourning rituals increased, mourning jewellery developed as a fashion item. Jet jewellery was worn a great deal by Queen Victoria after Prince Albert's death.
Jet from Whitby, North of England was set into mourning pieces. All types of material that were black were used and almost all included a lock of the dead loved one's hair. Hair was also plaited, braided or twisted very tightly until it became hard and thread like. To many of us living in the twenty first century the use of hair is an unattractive side of some antique jewellery.
Arts and Crafts Jewellery
The new design philosophy of Arts and Crafts that sprang up after 1870 was a reaction to mass produced goods and inferior machine made products. It was a reaction to the shoddy interior and ornamental products of the industrial revolution. Leaders of the movement in England included William Morris and John Ruskin and they promoted simple Arts and Crafts of designs based on floral, primitive or Celtic forms worked as wallpapers, furniture and jewellery.
The polished stones used in Arts and Crafts jewellery gave a medieval, simpler, gentler, tooled hand made look and feel to items. People inspired by the movement to produce work of a more individual nature included Liberty of London and Renee Mackintosh of Glasgow. By 1900, Arts and Crafts as a movement declined, so Art Nouveau, a more ostentatious version started in France took root.
Art Nouveau
Art Nouveau jewellery follows curving sinuous organic lines of romantic and imaginary dreaminess, with long limbed ethereal beauties sometimes turning into winged bird and flower forms. The movement began in Paris and its influence went throughout the Western world.
The Frenchman René Lalique was the master goldsmith of the era of Art Nouveau producing exquisite one off pieces. As an art movement today, the style is still admired and still copied.
Magnificent floral and botanical forms often worked in enamel were inexpensive and became so popular once mass-produced, that the Art Nouveau style declined.
Queen Alexandra's Pearls
Most fine jewellery in the 1900s was white and made from either diamonds or pearls. Queen Alexandra initially wore dog collar chokers, called a 'collier de chien' to cover a small scar on her neck.
Left - Queen Alexandra who wore pearls from neck to waist.
For state occasions and formal events she plastered herself in arrangements of pearl necklaces. The rarity value of real pearls then was such that an American skyscraper exchanged hands for the price of a pearl necklace.
This is not so ridiculous as it seems, as fine south sea pearls still command a high price.
TO TOP OF PAGE
Mikimoto Pearls
Pearls were very fashionable, but still very, very costly. After the 1890s Kokichi Mikimoto of Japan produced highly acceptable cultured pearls by placing a small bead into an oyster shell. The bead coated itself with nacre (mother of pearl) and so good looking pearl jewels became more affordable.
When I see Mikimoto pearls today I always think their lustre far surpasses any other pearl made this way.
Pearls
Various combinations of pearl necklaces come in and out of fashion with regularity so pearls too are a must. Both fake and real freshwater or cultured pearls are very affordable today. Many are now bought from China since trade opened up in the nineties. The price of pearls has dropped by about a fifth in the past 10 years and the Chinese are making waves in the pearl world with their cheaper prices. The Japanese have suffered disease in their pearl beds as well as facing competition and are finding it hard to compete with China's prices.
Pearl necklaces and pearl earrings can lift a complexion and bring light and radiance to the face taking years off a woman whatever her age. If you can afford it, invest in a pair of Mabe pearl earrings. They have a wonderful white glow with a size about one centimetre across and look expensive. Expect to pay about £300 for a pair trimmed with 9ct gold. Look after them by rubbing gently with a pure silk scarf, store in their original box and always put them on after applying perfume and hair products. A matching real pearl necklace freshwater or cultured, will enhance them and you.
Pearls are currently back in fashion again and with the modern twist of being interspaced on gold wire or floating on special synthetic cord they are essential to the millennium look. Look out for variations too on drop pearl earrings in the next year or so. PP
Cocktail Jewellery
In the 1920s Lalique designed good mass produced quality glass jewellery. Fake, or costume jewellery was sometimes then called cocktail jewellery. It was greatly influenced by Coco Chanel (1883-1971) and Elsa Schiaparelli (1890-1973). They both encouraged clients to use costume jewellery and to mix it with genuine gem pieces they already owned. Both designers offered imagination and fun and both often sported fabulous fakes.
In the late 1930s Napier of the USA was at the forefront of manufacturing fake cocktail jewels, which offered glamour and escapism. Napier still produces excellent contemporary costume pieces.
Hollywood Influence
By the 1940s and 1950s American culture was very dominant in Europe. The influence of movie films and the prominence of film stars set the fashion in manners, make-up, hair and clothes. People wanted look alike copies of outfits and jewellery worn by screen idols. It was widely believed that Hollywood glamour would rub off on you if you had the clothes and developed the look.
The Second World War in Europe halted production of fine jewellery when metals were rationed. New estate type, fine precious metal and gem jewellery was simply not available. Quality costume jewellery which was flourishing in America, became much more acceptable and was a real alternative to fine jewellery.
Because of technical advances in production methods, a huge range of styles was available from America, and since it was so popular the market became dynamic and inventive and affordable.
1980's Television Influence - Dynasty, Dallas and Diamante
In the 1980s there was a huge revival of costume jewellery after the glitzy scenes from the television soap operas Dynasty and Dallas were watched by 250 million viewers in the consumer boon of the 1980s. Diamante by day became the norm in reality and earrings reached such huge proportions that the 1990s saw a reaction which quickly dated lavish dress jewellery as the fashion for tiny real diamond studs or a fine stud pearls became the only earring to wear. As soon as the fashion was declared dead by everyone, including grandmothers, it was revived again in 2000AD by the fashion cognoscenti. Now fabulous fakes, especially brooches have gained ground once more.
Jewellery for the 21st Century
Costume jewellery can enliven a fashion wardrobe and bring a dash of panache especially for one off special occasions. Costume jewellery can be superb. The superb is usually plated at least seven times with 18 or 22 ct gold.
For example Joan Rivers does a range of good costume jewellery modelled on original fine gem pieces. One of her trademarks is to make jewellery doubly useful and she produces sets of interchangeable earrings, pendants and tennis bracelets. For example you might be able to slip a range of up to 10 different coloured stones, pearls or Swarovski crystals into an 18ct gold plated earring to vary the look. Her jewellery is exclusive to the QVC shopping channel in the UK and she is constantly working on new ideas such is her enthusiasm.
Highest grade Cubic Zirconium man made imitation diamonds often set in precious metals is of such a good standard that almost everyone can afford to have attractive jewellery.
The best crystals used in costume jewellery are the first grade crystals that the top Austrian firm Swarovski can offer. Butler and Wilson costume brooch.
Some of the costume jewellery I have come to love, comes from companies like Ciro, Adrian Buckley, Butler and Wilson, Swarovski Crystal Jewelry Napier, Joan Rivers, Joan Collins, Christian Dior, California Crystal, Property of A Lady and of course Kenneth J Lane.
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