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93-401: Kai Lung is a Chinese storyteller whose travels and exploits serve mainly as excuses to introduce substories, which generally take up the majority of a Kai Lung book. He is a man of very simple motivations; most frequently, he is animated by a desire for enough taels to be able to feed and clothe himself. Otherwise, his main motivation is love for his wife, Hwa-mei, and he seeks nothing more than

186-486: A bullet cast from silver is often supposed in such folklore the only weapon that is effective against a werewolf , witch , or other monsters . From this the idiom of a silver bullet developed into figuratively referring to any simple solution with very high effectiveness or almost miraculous results, as in the widely discussed software engineering paper " No Silver Bullet ." Other powers attributed to silver include detection of poison and facilitation of passage into

279-419: A color name . Protected silver has greater optical reflectivity than aluminium at all wavelengths longer than ~450 nm. At wavelengths shorter than 450 nm, silver's reflectivity is inferior to that of aluminium and drops to zero near 310 nm. Very high electrical and thermal conductivity are common to the elements in group 11, because their single s electron is free and does not interact with

372-470: A precious metal . Silver metal is used in many bullion coins , sometimes alongside gold : while it is more abundant than gold, it is much less abundant as a native metal . Its purity is typically measured on a per-mille basis; a 94%-pure alloy is described as "0.940 fine". As one of the seven metals of antiquity , silver has had an enduring role in most human cultures. Other than in currency and as an investment medium ( coins and bullion ), silver

465-753: A form of corruption and these taxes never reached the imperial government under the traditional fiscal regime. Near the end of the Qing dynasty, one dìng (sycee, or yuanbao ) is about 50 taels. The local tael took precedence over any central measure. Thus, the Canton tael weighed 37.5 grams (1.21 ozt), the Convention or Shanghai tael was 33.9 grams (1.09 ozt), and the Haiguan ( 海關 ; hǎiguān ; 'customs') tael 37.8 grams (1.22 ozt). The conversion rates between various common taels were well known. In

558-575: A non-Indo-European Wanderwort . Some scholars have thus proposed a Paleo-Hispanic origin, pointing to the Basque form zilharr as an evidence. The chemical symbol Ag is from the Latin word for silver , argentum (compare Ancient Greek ἄργυρος , árgyros ), from the Proto-Indo-European root * h₂erǵ- (formerly reconstructed as *arǵ- ), meaning ' white ' or ' shining ' . This

651-598: A reward for betrayal, references the bribe Judas Iscariot is said in the New Testament to have taken from Jewish leaders in Jerusalem to turn Jesus of Nazareth over to soldiers of the high priest Caiaphas. Ethically, silver also symbolizes greed and degradation of consciousness; this is the negative aspect, the perverting of its value. The abundance of silver in the Earth's crust is 0.08  parts per million , almost exactly

744-612: A scale unparalleled before the discovery of the New World . Reaching a peak production of 200 tonnes per year, an estimated silver stock of 10,000 tonnes circulated in the Roman economy in the middle of the second century AD, five to ten times larger than the combined amount of silver available to medieval Europe and the Abbasid Caliphate around AD 800. The Romans also recorded the extraction of silver in central and northern Europe in

837-450: A simple, sustainable lifestyle. Generally, he does not intrude in other people's affairs unless he thinks it necessary to teach them the rudiments of classical proportion with one of his fables. He usually comes into conflict with barbarians, bandits, and other people who are not classically educated, as well as various unscrupulous individuals who are intent on taking away his property. In Thorne Smith 's comedic fantasy The Stray Lamb ,

930-406: A single electron in the highest occupied s subshell over a filled d subshell, accounts for many of the singular properties of metallic silver. Silver is a relatively soft and extremely ductile and malleable transition metal , though it is slightly less malleable than gold. Silver crystallises in a face-centred cubic lattice with bulk coordination number 12, where only the single 5s electron

1023-621: A unit will typically abbreviate it as "tl". China's standard market tael (Chinese: 市两 ; pinyin: shìliǎng ) of 31.25 g was modified by the People's Republic of China in 1959. The new market tael was 50 g or 1 ⁄ 10 catty (500 g) to make it compatible with metric measures. (see Chinese unit for details.) In Shanghai, silver is still traded in taels. Some foodstuffs in China are sold in units also called "taels", but which do not necessarily weigh one tael. For cooked rice,

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1116-506: Is 1 + 1 ⁄ 3 oz. avoir. Similar to Hong Kong, in Singapore, one tael is defined as 1 + 1 ⁄ 3 ounce and is approximated as 37.7994 g The Taiwan tael is 37.5 g and is still used in some contexts. The Taiwan tael is derived from the tael or ryō ( 両 ) of the Japanese system (equal to 10 momme ) which was 37.5 g. Although the catty (equal to 16 taels)

1209-556: Is cognate with Old High German silabar ; Gothic silubr ; or Old Norse silfr , all ultimately deriving from Proto-Germanic *silubra . The Balto-Slavic words for silver are rather similar to the Germanic ones (e.g. Russian серебро [ serebró ], Polish srebro , Lithuanian sidãbras ), as is the Celtiberian form silabur . They may have a common Indo-European origin, although their morphology rather suggest

1302-465: Is the difluoride , AgF 2 , which can be obtained from the elements under heat. A strong yet thermally stable and therefore safe fluorinating agent, silver(II) fluoride is often used to synthesise hydrofluorocarbons . In stark contrast to this, all four silver(I) halides are known. The fluoride , chloride , and bromide have the sodium chloride structure, but the iodide has three known stable forms at different temperatures; that at room temperature

1395-470: Is Ag 3 O which behaves as a metallic conductor. Silver(I) sulfide , Ag 2 S, is very readily formed from its constituent elements and is the cause of the black tarnish on some old silver objects. It may also be formed from the reaction of hydrogen sulfide with silver metal or aqueous Ag ions. Many non-stoichiometric selenides and tellurides are known; in particular, AgTe ~3 is a low-temperature superconductor . The only known dihalide of silver

1488-438: Is because its filled 4d shell is not very effective in shielding the electrostatic forces of attraction from the nucleus to the outermost 5s electron, and hence silver is near the bottom of the electrochemical series ( E (Ag /Ag) = +0.799 V). In group 11, silver has the lowest first ionisation energy (showing the instability of the 5s orbital), but has higher second and third ionisation energies than copper and gold (showing

1581-632: Is commonly used at food markets where many items typically weigh in the 100–900 g range. However, a different tael (called cây , lạng , or lượng ) unit of 37.5 g is used for domestic transactions in gold. Real estate prices are often quoted in taels of gold rather than the local currency over concerns over monetary inflation . Silver Silver is a chemical element ; it has symbol Ag (from Latin argentum  'silver', derived from Proto-Indo-European *h₂erǵ ' shiny, white ' ) and atomic number 47. A soft, white, lustrous transition metal , it exhibits

1674-425: Is delocalised, similarly to copper and gold. Unlike metals with incomplete d-shells, metallic bonds in silver are lacking a covalent character and are relatively weak. This observation explains the low hardness and high ductility of single crystals of silver. Silver has a brilliant, white, metallic luster that can take a high polish , and which is so characteristic that the name of the metal itself has become

1767-549: Is higher than that of lead (1.87), and its electron affinity of 125.6 kJ/mol is much higher than that of hydrogen (72.8 kJ/mol) and not much less than that of oxygen (141.0 kJ/mol). Due to its full d-subshell, silver in its main +1 oxidation state exhibits relatively few properties of the transition metals proper from groups 4 to 10, forming rather unstable organometallic compounds , forming linear complexes showing very low coordination numbers like 2, and forming an amphoteric oxide as well as Zintl phases like

1860-413: Is much less stable, fuming in moist air and reacting with glass. Silver(II) complexes are more common. Like the valence isoelectronic copper(II) complexes, they are usually square planar and paramagnetic, which is increased by the greater field splitting for 4d electrons than for 3d electrons. Aqueous Ag , produced by oxidation of Ag by ozone, is a very strong oxidising agent, even in acidic solutions: it

1953-410: Is not reversible because the silver atom liberated is typically found at a crystal defect or an impurity site, so that the electron's energy is lowered enough that it is "trapped". White silver nitrate , AgNO 3 , is a versatile precursor to many other silver compounds, especially the halides, and is much less sensitive to light. It was once called lunar caustic because silver was called luna by

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2046-424: Is pale yellow, becoming purplish on exposure to light; it projects slightly from the surface of the artifact or coin. The precipitation of copper in ancient silver can be used to date artifacts, as copper is nearly always a constituent of silver alloys. Silver metal is attacked by strong oxidant such as potassium permanganate ( KMnO 4 ) and potassium dichromate ( K 2 Cr 2 O 7 ), and in

2139-415: Is rare in the periodic table. The atomic weight is 107.8682(2) u ; this value is very important because of the importance of silver compounds, particularly halides, in gravimetric analysis . Both isotopes of silver are produced in stars via the s-process (slow neutron capture), as well as in supernovas via the r-process (rapid neutron capture). Twenty-eight radioisotopes have been characterised,

2232-531: Is reflected in the relative decomposition temperatures of AgMe (−50 °C) and CuMe (−15 °C) as well as those of PhAg (74 °C) and PhCu (100 °C). The C–Ag bond is stabilised by perfluoroalkyl ligands, for example in AgCF(CF 3 ) 2 . Alkenylsilver compounds are also more stable than their alkylsilver counterparts. Silver- NHC complexes are easily prepared, and are commonly used to prepare other NHC complexes by displacing labile ligands. For example,

2325-430: Is similar in its physical and chemical properties to its two vertical neighbours in group 11 of the periodic table : copper , and gold . Its 47 electrons are arranged in the configuration [Kr]4d 5s , similarly to copper ([Ar]3d 4s ) and gold ([Xe]4f 5d 6s ); group 11 is one of the few groups in the d-block which has a completely consistent set of electron configurations. This distinctive electron configuration, with

2418-472: Is stabilised in phosphoric acid due to complex formation. Peroxodisulfate oxidation is generally necessary to give the more stable complexes with heterocyclic amines , such as [Ag(py) 4 ] and [Ag(bipy) 2 ] : these are stable provided the counterion cannot reduce the silver back to the +1 oxidation state. [AgF 4 ] is also known in its violet barium salt, as are some silver(II) complexes with N - or O -donor ligands such as pyridine carboxylates. By far

2511-463: Is still frequently used in Taiwan, the tael is only used for precious metals and herbal medicines. The Thai equivalent of the tael is known as the tamlueng , a term derived from Khmer . It was used as a unit of currency equal to four baht ; nowadays, as a unit of weight it is fixed at 60 grams. In French Indochina , the colonial administration fixed the tael ( lạng ) as 100 g, which

2604-413: Is the cubic zinc blende structure. They can all be obtained by the direct reaction of their respective elements. As the halogen group is descended, the silver halide gains more and more covalent character, solubility decreases, and the colour changes from the white chloride to the yellow iodide as the energy required for ligand-metal charge transfer (X Ag → XAg) decreases. The fluoride is anomalous, as

2697-614: Is used in solar panels , water filtration , jewellery , ornaments, high-value tableware and utensils (hence the term " silverware "), in electrical contacts and conductors , in specialised mirrors, window coatings, in catalysis of chemical reactions, as a colorant in stained glass , and in specialised confectionery. Its compounds are used in photographic and X-ray film. Dilute solutions of silver nitrate and other silver compounds are used as disinfectants and microbiocides ( oligodynamic effect ), added to bandages , wound-dressings, catheters , and other medical instruments . Silver

2790-726: Is used in vacuum brazing . The two metals are completely miscible as liquids but not as solids; their importance in industry comes from the fact that their properties tend to be suitable over a wide range of variation in silver and copper concentration, although most useful alloys tend to be richer in silver than the eutectic mixture (71.9% silver and 28.1% copper by weight, and 60.1% silver and 28.1% copper by atom). Most other binary alloys are of little use: for example, silver–gold alloys are too soft and silver– cadmium alloys too toxic. Ternary alloys have much greater importance: dental amalgams are usually silver–tin–mercury alloys, silver–copper–gold alloys are very important in jewellery (usually on

2883-482: Is usually obtained by reacting silver or silver monofluoride with the strongest known oxidising agent, krypton difluoride . Silver and gold have rather low chemical affinities for oxygen, lower than copper, and it is therefore expected that silver oxides are thermally quite unstable. Soluble silver(I) salts precipitate dark-brown silver(I) oxide , Ag 2 O, upon the addition of alkali. (The hydroxide AgOH exists only in solution; otherwise it spontaneously decomposes to

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2976-515: Is written 兩 (simplified as 两 ) and has the Mandarin pronunciation liǎng . The phrase "half a catty, eight taels" ( Chinese : 半斤八兩 , bàn jīn, bā liǎng ) is still used to mean two options are exactly equivalent, similar to the English "six of one, half a dozen of the other". In China, there were many different weighting standards of tael depending on the region or type of trade. In general

3069-843: The Koenigs–Knorr reaction . In the Fétizon oxidation , silver carbonate on celite acts as an oxidising agent to form lactones from diols . It is also employed to convert alkyl bromides into alcohols . Silver fulminate , AgCNO, a powerful, touch-sensitive explosive used in percussion caps , is made by reaction of silver metal with nitric acid in the presence of ethanol . Other dangerously explosive silver compounds are silver azide , AgN 3 , formed by reaction of silver nitrate with sodium azide , and silver acetylide , Ag 2 C 2 , formed when silver reacts with acetylene gas in ammonia solution. In its most characteristic reaction, silver azide decomposes explosively, releasing nitrogen gas: given

3162-532: The Lahn region, Siegerland , Silesia , Hungary , Norway , Steiermark , Schwaz , and the southern Black Forest . Most of these ores were quite rich in silver and could simply be separated by hand from the remaining rock and then smelted; some deposits of native silver were also encountered. Many of these mines were soon exhausted, but a few of them remained active until the Industrial Revolution , before which

3255-718: The Malay word tahil , meaning "weight". Early English forms of the name such as "tay" or "taes" derive from the Portuguese plural of tael, taeis . Tahil ( / ˈ t ɑː h ɪ l / in Singaporean English ) is used in Malay and English today when referring to the weight in Malaysia , Singapore , and Brunei , where it is still used in some contexts especially related to the significant Overseas Chinese population. In Chinese, tael

3348-646: The mythical realm of fairies . Silver production has also inspired figurative language. Clear references to cupellation occur throughout the Old Testament of the Bible , such as in Jeremiah 's rebuke to Judah: "The bellows are burned, the lead is consumed of the fire; the founder melteth in vain: for the wicked are not plucked away. Reprobate silver shall men call them, because the Lord hath rejected them." (Jeremiah 6:19–20) Jeremiah

3441-435: The platinum complexes (though they are formed more readily than those of the analogous gold complexes): they are also quite unsymmetrical, showing the weak π bonding in group 11. Ag–C σ bonds may also be formed by silver(I), like copper(I) and gold(I), but the simple alkyls and aryls of silver(I) are even less stable than those of copper(I) (which tend to explode under ambient conditions). For example, poor thermal stability

3534-526: The post-transition metals . Unlike the preceding transition metals, the +1 oxidation state of silver is stable even in the absence of π-acceptor ligands . Silver does not react with air, even at red heat, and thus was considered by alchemists as a noble metal , along with gold. Its reactivity is intermediate between that of copper (which forms copper(I) oxide when heated in air to red heat) and gold. Like copper, silver reacts with sulfur and its compounds; in their presence, silver tarnishes in air to form

3627-549: The silver tael weighed around 40 grams (1.3 ozt). The most common government measure was the Kuping ( 庫平 ; kùpíng ; 'treasury standard') tael, weighing 37.5 grams (1.21 ozt). A common commercial weight, the Caoping ( 漕平 ; cáopíng ; 'canal shipping standard') tael weighed 36.7 grams (1.18 ozt) of marginally less pure silver. As in China, other parts of East Asia such as Japan and Korea have also used

3720-766: The tahil and by other names , can refer to any one of several weight measures used in East and Southeast Asia . It usually refers to the Chinese tael, a part of the Chinese system of weights and currency . The Chinese tael was standardized to 50 grams in 1959. In Hong Kong and Singapore , it is equivalent to 10 mace (Chinese: 錢 ; pinyin: qián ) or 1 ⁄ 16 catty , albeit with slightly different metric equivalents in these two places. These Chinese units of measurement are usually used in Chinese herbal medicine stores as well as gold and silver exchange. The English word tael comes through Portuguese from

3813-702: The 19th century, primary production of silver moved to North America, particularly Canada , Mexico , and Nevada in the United States : some secondary production from lead and zinc ores also took place in Europe, and deposits in Siberia and the Russian Far East as well as in Australia were mined. Poland emerged as an important producer during the 1970s after the discovery of copper deposits that were rich in silver, before

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3906-568: The Greek and Roman civilisations, silver coins were a staple of the economy: the Greeks were already extracting silver from galena by the 7th century BC, and the rise of Athens was partly made possible by the nearby silver mines at Laurium , from which they extracted about 30 tonnes a year from 600 to 300 BC. The stability of the Roman currency relied to a high degree on the supply of silver bullion, mostly from Spain, which Roman miners produced on

3999-466: The Qing dynasty created a number of treaty ports alongside the China's main waterways and its coastal areas, these treaty ports would fundamentally change both the monetary system of China as well as its banking system , these changes were introduced by the establishment of European and American merchant houses and later banks that would engage in the Chinese money exchange and trade finance. Between

4092-446: The US, 13540 tons of silver were used for the electromagnets in calutrons for enriching uranium , mainly because of the wartime shortage of copper. Silver readily forms alloys with copper, gold, and zinc . Zinc-silver alloys with low zinc concentration may be considered as face-centred cubic solid solutions of zinc in silver, as the structure of the silver is largely unchanged while

4185-509: The Western powers had managed to take over the complete administration of the Qing's maritime customs from the imperial Chinese governmental bureaucracy. The Imperial Maritime Customs Service developed the Haikwan tael (海關兩), this new form of measurement was an abstract unit of silver tael that would become the nationwide standard unit of account in silver for any form of Customs tax. The Haikwan tael

4278-715: The allegedly Chinese proverb "It would be hypocrisy to seek for the person of the Sacred Emperor in a Low Tea House." It has been convincingly argued that Ford originally acquired this proverb from the Kai Lung novels of Ernest Bramah, and that Bramah had created it for Kai Lung, rather than quoting a genuine Chinese proverb. Irene the Librarian quotes Kai Lung in Genevieve Cogman’s novel “The Secret Chapter”. Tael Tael ( / ˈ t eɪ l / ), or liang , also known as

4371-553: The ancient alchemists, who believed that silver was associated with the Moon. It is often used for gravimetric analysis, exploiting the insolubility of the heavier silver halides which it is a common precursor to. Silver nitrate is used in many ways in organic synthesis , e.g. for deprotection and oxidations. Ag binds alkenes reversibly, and silver nitrate has been used to separate mixtures of alkenes by selective absorption. The resulting adduct can be decomposed with ammonia to release

4464-637: The black silver sulfide (copper forms the green sulfate instead, while gold does not react). While silver is not attacked by non-oxidising acids, the metal dissolves readily in hot concentrated sulfuric acid , as well as dilute or concentrated nitric acid . In the presence of air, and especially in the presence of hydrogen peroxide , silver dissolves readily in aqueous solutions of cyanide . The three main forms of deterioration in historical silver artifacts are tarnishing, formation of silver chloride due to long-term immersion in salt water, as well as reaction with nitrate ions or oxygen. Fresh silver chloride

4557-707: The centre of production returned to the Americas the following decade. Today, Peru and Mexico are still among the primary silver producers, but the distribution of silver production around the world is quite balanced and about one-fifth of the silver supply comes from recycling instead of new production. Silver plays a certain role in mythology and has found various usage as a metaphor and in folklore. The Greek poet Hesiod 's Works and Days (lines 109–201) lists different ages of man named after metals like gold, silver, bronze and iron to account for successive ages of humanity. Ovid 's Metamorphoses contains another retelling of

4650-427: The character Mr. Lamb relaxes while reading Kai Lung. Dorothy L. Sayers mentions Kai Lung and/or quotes from the books in several Lord Peter Wimsey novels, specifically Strong Poison , Gaudy Night and Busman's Honeymoon In "'He Cometh and He Passeth By!'" by H. Russell Wakefield , one of the principal characters reads The Wallet of Kai-Lung before retiring to bed. Ford Madox Ford repeatedly quoted

4743-434: The dominant producers of silver until around the beginning of the 18th century, particularly Peru , Bolivia , Chile , and Argentina : the last of these countries later took its name from that of the metal that composed so much of its mineral wealth. The silver trade gave way to a global network of exchange . As one historian put it, silver "went round the world and made the world go round." Much of this silver ended up in

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4836-408: The electron concentration rises as more zinc is added. Increasing the electron concentration further leads to body-centred cubic (electron concentration 1.5), complex cubic (1.615), and hexagonal close-packed phases (1.75). Naturally occurring silver is composed of two stable isotopes , Ag and Ag, with Ag being slightly more abundant (51.839% natural abundance ). This almost equal abundance

4929-411: The elements in groups 10–14 (except boron and carbon ) have very complex Ag–M phase diagrams and form the most commercially important alloys; and the remaining elements on the periodic table have no consistency in their Ag–M phase diagrams. By far the most important such alloys are those with copper: most silver used for coinage and jewellery is in reality a silver–copper alloy, and the eutectic mixture

5022-526: The exceptions are the nitrate, perchlorate, and fluoride. The tetracoordinate tetrahedral aqueous ion [Ag(H 2 O) 4 ] is known, but the characteristic geometry for the Ag cation is 2-coordinate linear. For example, silver chloride dissolves readily in excess aqueous ammonia to form [Ag(NH 3 ) 2 ] ; silver salts are dissolved in photography due to the formation of the thiosulfate complex [Ag(S 2 O 3 ) 2 ] ; and cyanide extraction for silver (and gold) works by

5115-422: The filled d subshell, as such interactions (which occur in the preceding transition metals) lower electron mobility. The thermal conductivity of silver is among the highest of all materials, although the thermal conductivity of carbon (in the diamond allotrope ) and superfluid helium-4 are higher. The electrical conductivity of silver is the highest of all metals, greater even than copper. Silver also has

5208-534: The fluoride ion is so small that it has a considerable solvation energy and hence is highly water-soluble and forms di- and tetrahydrates. The other three silver halides are highly insoluble in aqueous solutions and are very commonly used in gravimetric analytical methods. All four are photosensitive (though the monofluoride is so only to ultraviolet light), especially the bromide and iodide which photodecompose to silver metal, and thus were used in traditional photography . The reaction involved is: The process

5301-523: The formation of the complex [Ag(CN) 2 ] . Silver cyanide forms the linear polymer {Ag–C≡N→Ag–C≡N→}; silver thiocyanate has a similar structure, but forms a zigzag instead because of the sp - hybridized sulfur atom. Chelating ligands are unable to form linear complexes and thus silver(I) complexes with them tend to form polymers; a few exceptions exist, such as the near-tetrahedral diphosphine and diarsine complexes [Ag(L–L) 2 ] . Under standard conditions, silver does not form simple carbonyls, due to

5394-412: The free alkene. Yellow silver carbonate , Ag 2 CO 3 can be easily prepared by reacting aqueous solutions of sodium carbonate with a deficiency of silver nitrate. Its principal use is for the production of silver powder for use in microelectronics. It is reduced with formaldehyde , producing silver free of alkali metals: Silver carbonate is also used as a reagent in organic synthesis such as

5487-567: The gold-rich side) and have a vast range of hardnesses and colours, silver–copper–zinc alloys are useful as low-melting brazing alloys, and silver–cadmium– indium (involving three adjacent elements on the periodic table) is useful in nuclear reactors because of its high thermal neutron capture cross-section , good conduction of heat, mechanical stability, and resistance to corrosion in hot water. The word silver appears in Old English in various spellings, such as seolfor and siolfor . It

5580-454: The hands of the Chinese. A Portuguese merchant in 1621 noted that silver "wanders throughout all the world... before flocking to China, where it remains as if at its natural centre". Still, much of it went to Spain, allowing Spanish rulers to pursue military and political ambitions in both Europe and the Americas. "New World mines", concluded several historians, "supported the Spanish empire." In

5673-412: The highest electrical conductivity , thermal conductivity , and reflectivity of any metal . Silver is found in the Earth's crust in the pure, free elemental form (" native silver"), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite . Most silver is produced as a byproduct of copper , gold, lead , and zinc refining . Silver has long been valued as

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5766-407: The lowest contact resistance of any metal. Silver is rarely used for its electrical conductivity, due to its high cost, although an exception is in radio-frequency engineering , particularly at VHF and higher frequencies where silver plating improves electrical conductivity because those currents tend to flow on the surface of conductors rather than through the interior. During World War II in

5859-606: The metal. The situation changed with the discovery of cupellation , a technique that allowed silver metal to be extracted from its ores. While slag heaps found in Asia Minor and on the islands of the Aegean Sea indicate that silver was being separated from lead as early as the 4th millennium BC , and one of the earliest silver extraction centres in Europe was Sardinia in the early Chalcolithic period , these techniques did not spread widely until later, when it spread throughout

5952-434: The most important oxidation state for silver in complexes is +1. The Ag cation is diamagnetic, like its homologues Cu and Au , as all three have closed-shell electron configurations with no unpaired electrons: its complexes are colourless provided the ligands are not too easily polarised such as I . Ag forms salts with most anions, but it is reluctant to coordinate to oxygen and thus most of these salts are insoluble in water:

6045-546: The most stable being Ag with a half-life of 41.29 days, Ag with a half-life of 7.45 days, and Ag with a half-life of 3.13 hours. Silver has numerous nuclear isomers , the most stable being Ag ( t 1/2 = 418 years), Ag ( t 1/2 = 249.79 days) and Ag ( t 1/2 = 8.28 days). All of the remaining radioactive isotopes have half-lives of less than an hour, and the majority of these have half-lives of less than three minutes. Isotopes of silver range in relative atomic mass from 92.950 u ( Ag) to 129.950 u ( Ag);

6138-615: The official exchange rate between silver sycees and copper-alloy cash coins was set at 1,000 wén for 1 tael of silver before 1820, but after the year 1840 this official exchange rate was double to 2,000 wén to 1 tael. During the reign of the Xianfeng Emperor , the government of the Qing dynasty was forced to re-introduce paper money , among the paper money it produced were the Hubu Guanpiao (戶部官票) silver notes that were denominated in taels. The forced opening of China during

6231-573: The only objects with a high-enough palladium-to-silver ratio to yield measurable variations in Ag abundance. Radiogenic Ag was first discovered in the Santa Clara meteorite in 1978. Pd– Ag correlations observed in bodies that have clearly been melted since the accretion of the Solar System must reflect the presence of unstable nuclides in the early Solar System. Silver is a rather unreactive metal. This

6324-625: The ores of copper, copper-nickel, lead, and lead-zinc obtained from Peru , Bolivia , Mexico , China , Australia , Chile , Poland and Serbia . Peru, Bolivia and Mexico have been mining silver since 1546, and are still major world producers. Top silver-producing mines are Cannington (Australia), Fresnillo (Mexico), San Cristóbal (Bolivia), Antamina (Peru), Rudna (Poland), and Penasquito (Mexico). Top near-term mine development projects through 2015 are Pascua Lama (Chile), Navidad (Argentina), Jaunicipio (Mexico), Malku Khota (Bolivia), and Hackett River (Canada). In Central Asia , Tajikistan

6417-423: The oxide.) Silver(I) oxide is very easily reduced to metallic silver, and decomposes to silver and oxygen above 160 °C. This and other silver(I) compounds may be oxidised by the strong oxidising agent peroxodisulfate to black AgO, a mixed silver(I,III) oxide of formula Ag Ag O 2 . Some other mixed oxides with silver in non-integral oxidation states, namely Ag 2 O 3 and Ag 3 O 4 , are also known, as

6510-577: The photosensitivity of silver salts, this behaviour may be induced by shining a light on its crystals. Silver complexes tend to be similar to those of its lighter homologue copper. Silver(III) complexes tend to be rare and very easily reduced to the more stable lower oxidation states, though they are slightly more stable than those of copper(III). For instance, the square planar periodate [Ag(IO 5 OH) 2 ] and tellurate [Ag{TeO 4 (OH) 2 } 2 ] complexes may be prepared by oxidising silver(I) with alkaline peroxodisulfate . The yellow diamagnetic [AgF 4 ]

6603-961: The presence of potassium bromide ( KBr ). These compounds are used in photography to bleach silver images, converting them to silver bromide that can either be fixed with thiosulfate or redeveloped to intensify the original image. Silver forms cyanide complexes ( silver cyanide ) that are soluble in water in the presence of an excess of cyanide ions. Silver cyanide solutions are used in electroplating of silver. The common oxidation states of silver are (in order of commonness): +1 (the most stable state; for example, silver nitrate , AgNO 3 ); +2 (highly oxidising; for example, silver(II) fluoride , AgF 2 ); and even very rarely +3 (extreme oxidising; for example, potassium tetrafluoroargentate(III), KAgF 4 ). The +3 state requires very strong oxidising agents to attain, such as fluorine or peroxodisulfate , and some silver(III) compounds react with atmospheric moisture and attack glass. Indeed, silver(III) fluoride

6696-406: The primary decay mode before the most abundant stable isotope, Ag, is electron capture and the primary mode after is beta decay . The primary decay products before Ag are palladium (element 46) isotopes, and the primary products after are cadmium (element 48) isotopes. The palladium isotope Pd decays by beta emission to Ag with a half-life of 6.5 million years. Iron meteorites are

6789-419: The reaction of the bis(NHC)silver(I) complex with bis(acetonitrile)palladium dichloride or chlorido(dimethyl sulfide)gold(I) : Silver forms alloys with most other elements on the periodic table. The elements from groups 1–3, except for hydrogen , lithium , and beryllium , are very miscible with silver in the condensed phase and form intermetallic compounds; those from groups 4–9 are only poorly miscible;

6882-502: The region and beyond. The origins of silver production in India , China , and Japan were almost certainly equally ancient, but are not well-documented due to their great age. When the Phoenicians first came to what is now Spain , they obtained so much silver that they could not fit it all on their ships, and as a result used silver to weight their anchors instead of lead. By the time of

6975-697: The same as that of mercury . It mostly occurs in sulfide ores, especially acanthite and argentite , Ag 2 S. Argentite deposits sometimes also contain native silver when they occur in reducing environments, and when in contact with salt water they are converted to chlorargyrite (including horn silver ), AgCl, which is prevalent in Chile and New South Wales . Most other silver minerals are silver pnictides or chalcogenides ; they are generally lustrous semiconductors. Most true silver deposits, as opposed to argentiferous deposits of other metals, came from Tertiary period vulcanism. The principal sources of silver are

7068-669: The same time period. This production came to a nearly complete halt with the fall of the Roman Empire, not to resume until the time of Charlemagne : by then, tens of thousands of tonnes of silver had already been extracted. Central Europe became the centre of silver production during the Middle Ages , as the Mediterranean deposits exploited by the ancient civilisations had been exhausted. Silver mines were opened in Bohemia , Saxony , Alsace ,

7161-464: The shape and amount of extra detail on each ingot were highly variable; square and oval shapes were common but "boat", flower, tortoise and others are known. The tael was still used in Qing dynasty coinage as the basis of the silver currency and sycee remained in use until the end of the dynasty in 1911. Common weights were 50, 10, 5 and one tael. Before the year 1840 the government of the Qing dynasty had set

7254-422: The stability of the 4d orbitals), so that the chemistry of silver is predominantly that of the +1 oxidation state, reflecting the increasingly limited range of oxidation states along the transition series as the d-orbitals fill and stabilise. Unlike copper , for which the larger hydration energy of Cu as compared to Cu is the reason why the former is the more stable in aqueous solution and solids despite lacking

7347-445: The stable filled d-subshell of the latter, with silver this effect is swamped by its larger second ionisation energy. Hence, Ag is the stable species in aqueous solution and solids, with Ag being much less stable as it oxidises water. Most silver compounds have significant covalent character due to the small size and high first ionisation energy (730.8 kJ/mol) of silver. Furthermore, silver's Pauling electronegativity of 1.93

7440-411: The story, containing an illustration of silver's metaphorical use of signifying the second-best in a series, better than bronze but worse than gold: But when good Saturn , banish'd from above, Was driv'n to Hell, the world was under Jove . Succeeding times a silver age behold, Excelling brass, but more excell'd by gold. In folklore, silver was commonly thought to have mystic powers: for example,

7533-435: The tael ( Japanese : 両 ; rōmaji : ryō ; Korean : 량/냥 (兩) ; romaja : nyang/ryang ) as both a unit of weight and, by extension, a currency. Traditional Chinese silver sycees and other currencies of fine metals were not denominated or made by a central mint and their value was determined by their weight in taels. They were made by individual silversmiths for local exchange, and as such

7626-436: The various colonial powers and the government of the Qing dynasty. The Haikwan tael was on average 5% to 10% larger than the various local tael units that had existed in China, this was done as it deliberately excluded any form of extra surcharges which were embedded in the other units of the silver tael that existed as a form of intermediary income for local government tax collection, these surcharges were added to local taels as

7719-458: The weakness of the Ag–C bond. A few are known at very low temperatures around 6–15 K, such as the green, planar paramagnetic Ag(CO) 3 , which dimerises at 25–30 K, probably by forming Ag–Ag bonds. Additionally, the silver carbonyl [Ag(CO)] [B(OTeF 5 ) 4 ] is known. Polymeric AgLX complexes with alkenes and alkynes are known, but their bonds are thermodynamically weaker than even those of

7812-536: The weight of the tael is approximated using special tael-sized ladles. Other items sold in taels include the shengjian mantou and the xiaolongbao , both small bao buns commonly sold in Shanghai. In these cases, one tael is traditionally four and eight buns respectively. The tael is a legal weight measure in Hong Kong , and is still in active use. In Hong Kong, one tael is 37.799364167 g, and in ordinance 22 of 1884

7905-495: The world production of silver was around a meagre 50 tonnes per year. In the Americas, high temperature silver-lead cupellation technology was developed by pre-Inca civilisations as early as AD 60–120; silver deposits in India, China, Japan, and pre-Columbian America continued to be mined during this time. With the discovery of America and the plundering of silver by the Spanish conquistadors, Central and South America became

7998-577: The year 1933 the government of the Republic of China abolished the tael and completely replaced it with the yuan in a process known as the fei liang gai yuan ( 廢兩改元 ; 'Abolishing tael and changing to yuan'). During this time the Republican government cleared all banknotes denominated in the ancient tael currency, making all bills which used this currency unit obsolete. Modern studies suggest that, on purchasing power parity basis, one tael of silver

8091-469: The years 1840 and 1900, 1 market tael was worth 1.38 Spanish dollars . Various Western banking companies, the largest of which were the HSBC , and later Japanese banking companies started to begin to accept deposits. They would issue banknotes which were convertible into silver; these banknotes were popularized among the Chinese public that resided in the treaty ports. An important development during this era

8184-413: Was also aware of sheet silver, exemplifying the malleability and ductility of the metal: "Silver spread into plates is brought from Tarshish, and gold from Uphaz, the work of the workman, and of the hands of the founder: blue and purple is their clothing: they are all the work of cunning men." (Jeremiah 10:9) Silver also has more negative cultural meanings: the idiom thirty pieces of silver , referring to

8277-501: Was more often used ornamentally or as money. Since silver is more reactive than gold, supplies of native silver were much more limited than those of gold. For example, silver was more expensive than gold in Egypt until around the fifteenth century BC: the Egyptians are thought to have separated gold from silver by heating the metals with salt, and then reducing the silver chloride produced to

8370-454: Was preferred over the Kuping tael (庫平兩) by many merchants across China, this was because the units of the Kuping tael varied often to the advantage of imperial tax collectors, this form of corruption was an extra source of income for government bureaucrats at the expense of traders. The Haikwan tael unit was completely uniform, it was very carefully defined, and its creation had been negotiated among

8463-613: Was the establishment of the Imperial Maritime Customs Service . This agency was placed in charge of collecting transit taxes for traded goods that were shipped both in and out of the Chinese Empire, these rules and regulations were all stipulated in various trade treaties that were imposed on the Qing by the Western colonial powers. Because these changes were implemented during the height of the Taiping Rebellion ,

8556-457: Was the usual Proto-Indo-European word for the metal, whose reflexes are missing in Germanic and Balto-Slavic. Silver was known in prehistoric times: the three metals of group 11, copper, silver, and gold, occur in the elemental form in nature and were probably used as the first primitive forms of money as opposed to simple bartering. Unlike copper, silver did not lead to the growth of metallurgy , on account of its low structural strength; it

8649-426: Was worth about 4,130 yuan RMB in the early Tang dynasty , 2,065 yuan RMB in the late Tang dynasty , and 660.8 yuan RMB in the mid Ming dynasty . As of February 2024 the price of silver is about 254 yuan RMB/tael of 50 g. The tael is still in use as a weight measurement in a number of countries though usually only in limited contexts. In English-speaking countries, measurement scales that support Tael as

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