Gold

For example, gold is quite common in Turkey but considered a most valuable gift in Sicily. Perhaps the smallest hemispherical engine, the 4G12, a 1.2 L engine, was used in European and Middle Eastern Pony cars and pickups. The symbolic value of gold varies wildly around the world, even within geographic regions. They are I4, crossflow aluminum head, chaindriven 8 valve SOHC units. In Orthodox Christianity, the wedded couple is adorned with a golden crown during the ceremony, an amalgamation of symbolic rites. The largest being the 4G16 makes 101 hp (75 kW) @6000 rpm and 110 ft·lbf (149 N·m) @ 4000 rpm. 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. The "hemi" was used in other Chrysler cars (presumably in early model Dodge Lancers) as well as several mitsubishi vehicles.

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. In 1974, 4G14 (1,436 cc, 89.8 in³) unit (indeed, its entire driveline) was used by Hyundai Motor Company to power the Pony, until 1983 when the 4G16 (1,597 cc, roughly 99 in³) was used in the Stellar, and in 1985 on the PonyII. 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 Emmy Awards and the British Academy Film Awards). The spark plugs were not in the centre of the dome, but slightly off to the exhaust side. Great human achievements are frequently rewarded with gold, in the form of medals and decorations. Its displacement was very small, a 1.3 liter motor. Gold is associated with notable anniversaries, particularly in a 50 year cycle, such as a golden wedding anniversary, golden jubilee, etc. Beginning production circa 1969 was the 4G13, a prototype engine used in the first Mitsubishi Lancer.

On the other hand, eminent orators such as John Chrysostom were said to have a mouth of gold with a silver tongue. The classic Hemi engines of the 1960s featured true hemispherical heads, and splayed (perpendicular) valves. American Indians of the Sioux tribe called it "The yellow metal that makes the white man crazy". some notable engines designed and used by Porsche in both customer production car and Race cars:. 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. The basic design did not change much until 1996, when Porsche moved to water cooling. The Golden Calf is a widely-recognised symbol of idolatry and revolt against God. When Porsche introduced the 911, it had a 2.0 L flat-6 engine, with hemispherical heads.

Gold has been associated with the extremities of utmost evil and great sanctity throughout history. Also, at the 2005 SEMA show, Chrysler unvieled a 505-horsepower 6.4L HEMI which will be available as a crate engine and might find its way into production, perhaps with reduced horsepower. Gold used in dentistry is widely regarded as the safest form of restorative material, as well as the most successful. Some versions of the 5.7L, including most 2006 production units, utilise a variable displacement technology called the Multi-Displacement System (MDS) to improve fuel economy. Liver and kidney damage has, however, been reported for up to 50% of arthritis patients treated with gold-containing drugs. It is available in two sizes; 5.7 and 6.1 liters. The human body does not absorb gold very well, thus compounds of gold are not normally very toxic. This engine replaced Chrysler's large LA family of engines, particularly the Magnum 5.9, in the early 2000s.

There is only one stable isotope of gold, and 18 radioisotopes with Au-195 being the most stable with a half-life of 186 days. This engine is not a true hemispherical head engine; it has a polyspherical combustion chamber, but retains the Hemi's traditional inline perpendicular valves. Gold also forms:. Chrysler introduced a modern Hemi in 2002. Such compounds containing the Au^- anion are called aurides and include caesium auride, CsAu, rubidium auride, RbAu, and tetramethylammonium auride, (CH₃)₄N⁺ Au^-. Hemi.com provides information on three eras of Hemi power: 1951 to 1959, 1964 to 1971 and 2002 to current. Gold also can under extreme conditions form a +5 state with fluorine (gold pentafluoride, AuF₅), as well as (unusually for a metal), a -1 state. Racers like "Big Daddy" Don Garlits have set many world records using Hemi power.

Gold compounds can be aurous (univalent, +1) or auric (trivalent, +3). The Hemi head design is so efficient and effective that it was, and is, a top performer in NHRA, IHRA, UDRA and other sanctioned drag racing events throughout the world. Although gold is a noble metal, it can form many compounds, auric chloride (AuCl₃) and chlorauric acid (HAuCl₄) being the most common. Hemi blocks were traditionally painted orange to distinguish them from other V8s. Roosevelt expropriated gold by Executive Order 6102, and President Richard Nixon closed the gold window by which foreign countries could exchange American dollars for gold at a fixed rate. It was available in most Mopar muscle cars and pony cars of the period, although its high price and limited street tractability kept sales fairly low. President Franklin D. The engine was available through 1971, and the DaimlerChrysler corporation still sells crate engines and parts.

Within the United States, the private possession of gold except as jewelry and coin collecting was banned between 1933 and 1975. It was based on the Chrysler RB engine big-block. Because of its use as a reserve store of value, the possession of gold is sometimes restricted or banned. In 1964, Chrysler introduced a new 426 in³ (7.0 L) Hemi, designed to win at NASCAR racing and sold to the public to meet homologation requirements and to enable the public to buy the winning engine. Prices have risen to the $570/oz ($18,300/kg) mark in early 2006 [3]. This design, the Chrysler FirePower engine, was used until 1959. 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). Experience with this engine led to Chrysler using the Hemi design for their first overhead valve V8 in 1951.

Federal Reserve Bank, in New York. Chrysler's first experience with the Hemi design was during World War 2, in which it developed an experimental 2500 hp (1864 kW) V16 engine for the P-47 Thunderbolt. The largest gold depository in the world is that of the U.S. . Central banks still hold historical gold reserves as a store of value although the level has generally been declining. Other manufacturers used the hemispherical design before World War II, including Daimler and Riley. On March 17, 1968, economic circumstances caused the collapse of the gold pool, and a two-tiered pricing scheme was established whereby gold was still used to settle international accounts at the old $35.00 per troy ounce ($1.13/g) but the price of gold on the private market was allowed to fluctuate; this two-tiered pricing system was abandoned in 1975 when the price of gold was left to find its free-market level. Jaguar used this head design as well on the legendary XK engines, which powered cars ranging from the Le Mans winning D-Type to the XJ6 sedan.

By 1961 it was becoming hard to maintain this price, and a pool of US and European banks began to act together to defend the price against market forces. Porsche has also been a notable user of the Hemi design, generating up to 86 hp per liter displacement on production cars (1973 2.4 L 911S), and even more on racing engines (906 Carrera engine). For a long period the United States government set the price of gold at $20.67 per troy ounce ($664.56/kg) but in 1934 the price of gold was set at $35.00 per troy ounce ($1125.27/kg). Chrysler has used the word "Hemi" extensively in its advertising, to the extent that the word is indelibly associated with Chrysler in North America. As part of this system, governments and central banks attempted to control the price of gold by setting values at which they would exchange it for currency. Perhaps the best-known proponent of the Hemi design has been the Chrysler Corporation, who have produced three generations of such engines: the first (the Chrysler FirePower engine) in the 1950s; the second (the 426 Hemi) from the mid 1960s through the mid 1970s; and finally in the early 2000s. Historically gold was used to back currency in an economic system known as the gold standard in which one unit of currency was equivalent to a certain weight of gold. Most applications have been in higher-priced luxury or sporting vehicles, because the hemi design is more expensive to build.

The price of gold is determined on the open market, but a procedure known as the Gold Fixing in London, originating in 1919, provides a twice-daily benchmark figure to the industry. Hemispherical cylinder heads have been used in some engines since they were first used by the Belgian car maker Pipe in 1905. 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. Placing the intake on the opposite side of the engine also reduces the air intake temperature and increases efficiency. When it is alloyed with other metals the term carat or karat is used to indicate the amount of gold present, with 24 carats being pure gold and lower ratings proportionally less. The hemispherical cylinder head increases the engine's efficiency through reduced thermal energy loss and increased airflow through the engine, but drawbacks such as increased production cost has meant that it has been a rare design. Like other precious metals, gold is measured by troy weight and by grams. These aspects help make the hemi-type engine more efficient and powerful, and less prone to engine knock.

No commercially viable mechanism for performing gold extraction from sea water has yet been identified. The spark plug in the center of the chamber makes for better ignition of the fuel/air mixture. The effort produced little gold and cost the German government far more than the commercial value of the gold recovered. The hemispherical combustion chamber design puts the intake/exhaust valves in-line, rather than side-by-side, allowing for better flow of air through the head (although the inlet and exhaust valves are not simultaneously open and there is no continuous flow). Unfortunately, his assessment of the concentration of gold in sea water was unduly high, probably due to sample contamination. Chrysler's main innovation was to build them in such large numbers. 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. Stutz had built four valve engines, resembling modern car engines.

The world's oceans hold a vast amount of gold, but in very low concentrations (perhaps 1-2 parts per billion). Harry Arminius Miller racing engines were more notable example. The possibility of cheap man-made gold would have unforeseen economic and political consequences. The BMW double push rod design, taken over by Bristol Cars, and the Peugeot 403 are other well known examples. No economically feasible method to manufacture gold artificially has been found and published yet. The term, "Hemi engine", is a trademark of Chrysler Corporation, though the concept is used by many manufacturers. However, it is possible to obtain infinitesimally small amounts of gold by artificial nuclear transformations in particle accelerators The gold isotopes produced would likely be radioactive. Hemi (from "hemisphere") or "crossflow cylinder head" is a design of internal-combustion engines in which the cylinder head's combustion chamber is of hemispherical form.

Modern science has since proven the impossibility of making gold from other elements via chemical reactions. porcelain), while searching in vain for the philosopher's stone, which was supposed to turn mercury into gold. Scientists, kings and charlatans obsessed with the secret art of alchemy accidentally invented practically useful materials (e.g. The idea of producing gold out of lesser metals or other cheap substances has fascinated people throughout the centuries.

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. After initial production, gold is often subsequently refined industrially by the Wohlwill process or the Miller process. In South America, the controversial project Pascua Lama aims at exploitation of rich fields in the high mountains of Atacama, at the border between Chile and Argentina. Kolar Gold Fields in India is another example of a city being built on the greatest gold deposits in India.

Siberian regions of the USSR also used to be significant in the global gold mining industry. Mines in South Dakota and Nevada supply two-thirds of gold used in the United States. Other major producers are Canada, United States and Western Australia. The Second Boer War of 1899–1901 between the British Empire and the white Boers was at least partly over the rights of miners and possession of the gold wealth in South Africa.

Gold fields in the Orange Free State and the Transvaal are deep and require the world's deepest mines. The city of Johannesburg was built atop the world's greatest gold finds. This decline was due to the increasing difficulty of extraction and changing economic factors affecting the industry in South Africa. Production in 1970 accounted for 79% of the world supply, producing about 1,000 tonnes, however production in 2004 was 342 tonnes.

Since the 1880s South Africa has been the source for a large proportion of the world's gold supply. It is claimed, that all the gold that has been mined throughout the history of mankind could be incorporated in a solid ball with a diameter of 27 metres. Ore grades of 30 g/1000 kg (30 ppm) are usually needed before gold is visible to the naked eye, therefore in most gold mines you will not see any gold. 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.

Gold occurs in sea water at 0.1 to 2 mg/t (0.1 to 2 ppb by weight) depending on sample location. Another important ore type is in sedimentary black shale and limestone deposits containing finely disseminated gold and other platinum group metals. In all these deposits the gold is in its native form. Primary deposits can be weathered and eroded, with most of the gold being transported into stream beds where it congregates with other heavy minerals to form placer deposits.

There are several primary deposit types, common ones are termed reef or vein. A deposit usually needs some form of secondary enrichment to form an economically viable ore deposit: either chemical or physical processes like erosion or solution or more generally metamorphism, which concentrates the gold in sulfide minerals or quartz. The primary source of gold is usually igneous rocks or surface concentrations. Hydrothermal ore deposits of gold occur in metamorphic rocks and igneous rocks; alluvial deposits and placer deposits originate from these sources.

Gold is widely distributed in the Earth's crust at a background level of 0.03 g/1000 kg (0.03 ppm by weight). Rarer mineral associations are petzite, calaverite, sylvanite, muthmannite, nagyagite and krennerite. The most common sulfide associations are pyrite, chalcopyrite, galena, sphalerite, arsenopyrite, stibnite and pyrrhotite. Common gold associations are quartz often as veins and sulfide minerals.

These grains occur between mineral grain boundaries or as inclusions within minerals. Occasionally large accumulations of native gold (also known as nuggets) occur but usually gold occurs as minute grains. Due to its relative chemical inertness gold is usually found as the native metal or alloy. Because of its historically high value, much of the gold mined throughout history is still in circulation in one form or another.

During the 19th century, gold rushes occurred whenever large gold deposits were discovered, including the California, Colorado, Otago, Australia, Witwatersrand, Black Hills, and Klondike gold rushes. For modern attempts to produce artificial gold, see gold synthesis. 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). 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.

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. Gold in antiquity was relatively easy to obtain geologically; however, 75% of all gold ever produced has been extracted since 1910.[2] 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) a side. Gold has been used as a symbol for purity, value, royalty, and particularly roles that combine these properties (see gold album). Gold has long been considered one of the most precious metals, and its value has been used as the standard for many currencies (known as the gold standard) in history.

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. 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 south-east corner of the Black Sea was famed for its gold. Gold is also mentioned several times in the Old Testament.

Egypt and Nubia had the resources to make them major gold-producing areas for much of history. Egyptian hieroglyphs from as early as 2600 BC describe gold, which king Tushratta of the Mitanni claimed was as "common as dust" in Egypt. It may have been the first metal used by humans and was valued for ornamentation and rituals. Gold ( Sanskrit jval, Greek χρυσóς [khrisós], Latin aurum for "shining dawn", Anglo-Saxon gold, Chinese 金 [jīn],Japanese 金 [kin] ) has been known and highly valued since prehistoric times.

Because of its high electrical conductivity and resistance to corrosion and other desirable combinations of physical and chemical properties, gold also emerged in the late 20th century as an essential industrial metal. Gold and its many alloys are most often used in jewelry, coinage and as a standard for monetary exchange in many countries. Pure gold is too soft for ordinary use and is hardened by alloying with silver, copper, and other metals. [1].

Recent research undertaken by Frank Reith of the Australian National University shows that microbes play an important role in the formation of gold deposits, transporting and precipitating gold to form grains and nuggets that collect in alluvial deposits. The added metal is oxidized and dissolves allowing the gold to be displaced from solution and be recovered as a solid precipitate. Gold ions in solution are readily reduced and precipitated out as gold metal by the addition of virtually any other metal as the reducing agent. Common oxidation states of gold include +1 (gold(I) or aurous compounds) and +3 (gold(III) or auric compounds).

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. Gold is a good conductor of heat and electricity, and is not affected by air and most reagents. As the amount of silver increases, the color becomes whiter and the specific gravity lower. Native gold contains usually eight to ten per cent silver, but often much more — alloys with a silver content over 20% are called electrum.

Adding copper yields a redder metal, iron blue, Silver produces green, aluminium purple, platinum metals white, and natural bismuth together with silver alloys produce black. This can be done to increase its strength, or create several exotic colors, sold for instance in the western United States to the tourist trade as "Black Hills" gold. A soft metal, gold will readily form alloys with many other metals. It is the most malleable and ductile metal known; a single gram can be beaten into a sheet of one square metre, or an ounce into 300 square feet.

Only silver colloids exhibit the same interactions with light, albeit at a shorter frequency, making silver colloids yellow in color. These colors are the result of gold's plasmon frequency lying in the visible range, which causes red and yellow light to be reflected, and blue light to be absorbed. Gold is a metallic element with a characteristic yellow color, but can also be black or ruby when finely divided, while colloidal solutions are intensely colored and often purple. .

Its ISO currency code is XAU. Gold forms the basis for a monetary standard used by the International Monetary Fund (IMF) and the Bank for International Settlements (BIS). For millennia, gold has served as money and is also used in jewelry, dentistry, and in electronics. The metal occurs as nuggets or grains in rocks and in alluvial deposits and is one of the coinage metals.

A soft, shiny, yellow, dense, malleable, ductile (trivalent and univalent) transition metal, gold does not react with most chemicals but is attacked by chlorine, fluorine and aqua regia. Gold is a chemical element in the periodic table that has the symbol Au (from the Latin aurum) and atomic number 79. The Columbia Electronic Encyclopedia, 6th ed. Los Alamos National Laboratory – Gold.

Gold hydrazide: an olive-green powder, AuN₂H₃, one of several explosive compounds known archaically as aurum fulminans. Gold cluster compounds. Gold chalcogenides (O, S, Se,Te). Gold halides (F,Cl,Br,I).

The AuCl₄^- ion after dissolving in aqua regia. Green gold (a gold/silver alloy) is used in specialized jewelry while gold alloys with copper (reddish color) are more widely used for that purpose (rose gold)*. White gold (an alloy of gold with platinum, palladium, nickel, and/or zinc) serves as a substitute for platinum. Only the salts and radioisotopes (mentioned above) have any evidence of medicinal value.

For similar reasons, it also used as the basis for some superstitious, over the top, health claims. Some use it as an excuse to create super-expensive delicacies ($1,000 cocktails). Having no reactivity it adds no taste but is taken as a delicacy. Called varak or (varaq) in India.

Gold flake is used on and in some gourmet sweets and drinks. The gold isotope Au-198, (half-life: 2.7 days) is used in some cancer treatments and for treating other diseases. However, it can also cause photosensitive rashes, gastrointestinal disturbance, and kidney damage. It inhibits lymphocyte proliferation, lysosomal enzyme release, the release of reactive oxygen species from macrophages, and IL-1 production.

Disodium aurothiomalate is a treatment for rheumatoid arthritis (administered intramuscularly). Since it is a good reflector of both infrared and visible light, it is used for the protective coatings on many artificial satellites. Many competitions and honors, such as the Olympics and the Nobel Prize, award a gold medal to the winner (with silver to the second-place finisher, and bronze to the third.). Gold is used as a coating enabling biological material to be viewed under a scanning electron microscope.

It is also the usual starting point for making other gold compounds. Gold(III) chloride is used as a catalyst in organic chemistry. Chlorauric acid is used in photography for toning the silver image. It is also the form used as gold paint on ceramics prior to firing.

Colloidal gold (a gold nanoparticle) is an intensely colored solution that is currently studied in many labs for medical, biological and other applications. Gold is used in restorative dentistry especially in tooth restorations such as crowns and bridges. The resistance to oxidation of gold has led to its widespread use as thin layers electroplated on the surface of electrical connectors to ensure a good connection. Gold performs critical functions in computers, communications equipment, spacecraft, jet aircraft engines, and a host of other products.

Gold can be made into thread and used in embroidery.