silver

Dictionary: sil·ver   (sĭl'vər)

1. (Symbol Ag) A lustrous white, ductile, malleable metallic element, occurring both uncombined and in ores such as argentite, having the highest thermal and electrical conductivity of the metals. It is highly valued for jewelry, tableware, and other ornamental use and is widely used in coinage, photography, dental and soldering alloys, electrical contacts, and printed circuits. Atomic number 47; atomic weight 107.87; melting point 960.8°C; boiling point 2,212°C; specific gravity 10.50; valence 1, 2.
2. This metallic element as a commodity or medium of exchange.
3. Coins made of this metallic element.
4. A medal made of silver awarded to one placing second in a competition, as in the Olympics.
5. 1. Domestic articles, such as tableware, made of or plated with silver.
   2. Tableware, especially eating and serving utensils, made of steel or another metal.
6. A lustrous medium gray.
7. A silver salt, especially silver nitrate, used to sensitize paper.

1. Made of or containing silver: a silver bowl; silver ore.
2. Resembling silver, especially in having a lustrous shine; silvery.
3. Of a lustrous medium gray: silver hair.
4. Having a soft, clear, resonant sound.
5. Eloquent; persuasive: a silver voice.
6. Favoring the adoption of silver as a standard of currency: the silver plank of the 1896 Democratic platform.
7. Of or constituting a 25th anniversary.

1. To cover, plate, or adorn with silver or a similar lustrous substance.
2. To give a silver color to.
3. To coat (photographic paper) with a film of silver nitrate or other silver salt.

To become silvery.

[Middle English, from Old English siolfor, seolfor, probably ultimately from Akkadian ṣarpu, refined silver, verbal adj. of ṣarāpu, to smelt, refine.]

Background

Silver was one of the earliest metals known to humans, and it has been considered a precious metal since ancient times. Silver has been used as a form of currency by more people throughout history than any other metal, even gold. Although it is usually found in ores with less rare metals, such as copper, lead, and zinc, silver was apparently discovered in nugget form, called native silver, about 4000 B.C. Silver utensils and ornaments have been found in ancient tombs of Chaldea, Mesopotamia, Egypt, China, Persia, and Greece. In more recent times, the principal uses for silver were coinage and silverware.

In 1993, worldwide production of silver from mines totaled 548.2 million ounces (15.5 billion grams). During that year, Mexico was the world's largest producer of silver, with a total production of 75.7 million ounces (2.1 billion grams). The United States was the second leading producer, followed by Canada, Australia, Spain, Peru, and Russia. The vast majority of the world's silver is used in industrial applications, and the United States is the leading consumer. Other top consumers include Japan, India, and eastern European countries.

Silver mining in North America dates back to the eighteenth century. Around 1800, production began in the United States on the east coast and then moved west. The mining of silver was instrumental in the settlement of the state of Nevada. In 1994, Nevada was the largest producer of silver in the United States; Nevada mines produced 22.8 million troy ounces (709 million grams) of silver. Arizona, California, and Nevada are known for large-tonnage, low-grade silver deposits.

Physical Characteristics and Uses of Silver

Silver is the whitest metallic element. It is rare, strong, corrosion resistant, and unaffected by moisture, vegetable acids, or alkalis. Silver is also resonant, moldable, malleable, and possesses the highest thermal and electric conductivity of any substance. The chemical symbol for silver is Ag, from the Latin argentum, which means white and shining. Although silver does not react to many chemicals, it does react with sulfur, which is always present in the air, even in trace amounts. The reaction causes silver to tarnish, therefore, it must be polished periodically to retain its luster.

Silver possesses many special physical characteristics and qualities that make it useful in a variety of industries. The photography industry is the biggest user of silver compounds. Silver forms the most light-sensitive salts, or halides, which are essential to developing high-quality photography. Silver has the highest electrical conductivity per unit volume of any metal, including copper, so it is used extensively in electronics. Specialized uses include switch and relay contacts for automobile controls and accessories, automotive window heating, and in electrodes for electrocardiograms.

Silver is one of the strongest oxidants, making it an essential catalyst for the chemical process industry. It is used in the production of adhesives, dinnerware, mylar recording tape, and many other products. Silver is the most reflective of all metals, and is used to coat glass in mirrors. It is also used in x-ray vacuum tubes and as material for bearings. With the highest level of thermal conductivity among metals and resistance to combustion and sparks, silver is a valuable material for a range of other industrial processes. The most common consumer application of silver is its use in jewelry. Pure silver, which would be too soft to be durable, is mixed with 5-20% copper in an alloy known as sterling silver.

Today, a very small percentage of the world's silver is used in coinage, though silver coins were a popular form of currency until the recent past. As industrialized nations began to produce large numbers of silver coins in the twentieth century, silver became less available, and therefore more expensive. The United States Treasury, which until then had been minting 90% silver coins, changed their minting by a 1965 act of Congress. The Johnson Silver Coinage Act completely demonetized silver, and with the exception of bicentennial coins, all newly-minted United States coins are now made of an alloy of copper and nickel.

The Manufacturing
Process

Silver was first obtained in sixteenth-century Mexico by a method called the patio process. It involved mixing silver ore, salt, copper sulphide, and water. The resultant silver chloride was then picked up by adding mercury. This inefficient method was superseded by the von Patera process. In this process, ore was heated with rock salt, producing silver chloride, which was leached out with sodium hyposulfite. Today, there are several processes used to extract silver from ores.

A method called the cyanide, or heap leach, process has gained acceptance within the mining industry because it is a low-cost way of processing lower-grade silver ores. However, the ores used in this method must have certain characteristics: the silver particles must be small; the silver must react with cyanide solutions; the silver ores must be relatively free of other mineral contaminants and/or foreign substances that might interfere with the cyanidation process; and the silver must be free from sulfide minerals. The idea for cyanidation actually dates back to the eighteenth century, when Spanish miners percolated acid solutions through large heaps of copper oxide ore. The process developed into its present form during the late nineteenth century. The cyanide process is described here.

Preparing the ore

• Silver ore is crushed into pieces, usually with 1-1.5 in (2.5-3.75 cm) diameters, to make the material porous. Approximately 3-5 lb (1.4-2.3 kg) of lime per ton of silver ore is added to create an alkaline environment. The ore must be completely oxidized so the precious metal is not confined in sulfide minerals. Where fines or clays exist, the ore is agglomerated to create a uniform leach pile. This process consists of crushing the ore, adding cement, mixing, adding water or a cyanide solution, and curing in dry air for 24-48 hours.
• Broken or crushed ore is stacked on impermeable pads to eliminate the loss of the silver cyanide solution. Pad material may be asphalt, plastic, rubber sheeting, and/or clays. These pads are sloped in two directions to facilitate drainage and the collection of the solutions.

Adding the cyanide solution and curing

• A solution of water and sodium cyanide is added to the ore. Solutions are delivered to the heaps by sprinkler systems or methods of ponding, including ditches, injection, or seepage from capillaries.

Recovering the silver

• Silver is recovered from heap leach solutions in one of several ways. Most common is Merrill-Crowe precipitation, which uses fine zinc dust to precipitate the precious metal from the solution. The silver precipitate is then filtered off, melted, and made into bullion bars.
• Other methods of recovery are activated carbon absorption, where solutions are pumped through tanks or towers containing activated carbon, and the addition of a sodium sulfide solution, which forms a silver precipitate. In another method, the solution is passed through charged resin materials which attract the silver. The recovery method is generally decided based on economic factors.

Silver is rarely found alone, but mostly in ores which also contain lead, copper, gold, and other metals which may be commercially valuable. Silver emerges as a byproduct of processing these metals. To recover silver from zinc-bearing ores, the Parkes process is used. In this method, the ore is heated until it becomes molten. As the mixture of metals is allowed to cool, a crust of zinc and silver forms on the surface. The crust is removed, and the metals undergo a distillation process to remove the zinc from the silver.

To extract silver from copper-containing ores, an electrolytic refining process is used. The ore is placed in an electrolytic cell, which contains a positive electrode, or anode, and a negative electrode, or cathode, in an electrolyte solution. When electricity is passed through the solution, silver, with other metals, accumulates as a slime at the anode while copper is deposited on the cathode. The slimes are collected, then roasted, leached, and smelted to remove impurities. The metals are formed into blocks which are used as anodes in another round of electrolysis. As electricity is sent through a solution of silver nitrate, pure silver is deposited onto the cathode.

The Future

How much silver will be produced in the future depends on many factors, including the rate of production of other metals and future uses of silver. Industrial demand for silver appears to be steady overall. Because silver naturally occurs with other metals, future production is linked to the production of copper, lead, gold, and zinc.

In the future, silver will likely continue to be used for special industrial applications, as well as for consumer items, such as jewelry and silverware. In addition to these traditional uses, the value of silver will also depend on new uses for the metal. For example, using silver as a sanitizing agent is currently under development. Manufacturers have hustled in response to studies by the Atlanta-based Center for Disease Control that many viruses, including those linked to Acquired Immunodeficiency Syndrome (AIDS), will survive briefly outside an individual in fluids deposited on surfaces of plastic products, such as telephones. Matsushita Electric Industrial Co., Ltd. in Osaka, Japan, completed a project at the Research Institute for Microbial Diseases, Osaka University, to produce a surface treatment that provides long-lasting sanitization for its plastic products. Research revealed the most effective system to be a compound based on silver thiosulfate.

Currently marketed under the name Amenitop, the system consists of silica gel microspheres that contain a silver thiosulfate complex. The silica gel coating allows a gradual release of the silver compound onto the surface, which provides long-lasting sanitization. Studies suggest that Amenitop kills bacteria and viruses by destroying the cell's membranes.

Where to Learn More

Books

Coombs, Charles. Gold and Other Precious Metals. William Morrow and Company, 1981.

Robbins, Peter and Douglass Lee. Guide to Precious Metals and Their Markets. Nichols Publishing, 1979.

Smith, Jerome F. and Barbara Kelly Smith. What's Behind the New Boom In Silver and How to Maximize Your Profits. Griffin Publishing Company, 1983.

Periodicals

"A Listing of the End Users of Silver By Property." The Silver Institute, January 13, 1994, pp. 1-14.

"A Nevada Leader." News from Las Vegas (Las Vegas News Bureau), March 1995, p. 1.

"New Silver Compound To Fight Spread of Viruses." The Silver Institute Letter, December 1994-January 1995, pp. 1, 2,4.

Thorstad, Linda E. "How Heap Leaching Changed The West." World Investment News, February 1987, pp. 31, 33.

[Article by: Susan Bard Hall]

A chemical element, Ag, atomic number 47, atomic mass 107.868. It is a gray-white, lustrous metal. Chemically it is one of the heavy metals and one of the noble metals; commercially it is a precious metal. There are 25 isotopes of silver with atomic masses ranging from 102 to 117. Ordinary silver is made up of the isotopes of masses 107 (52% of natural silver) and 109 (48%). See also Periodic table.

Although silver is the most active chemically of the noble metals, it is not very active in comparison with most other elements. It does not oxidize as iron does when it rusts, but it reacts with sulfur or hydrogen sulfide to form the familiar silver tarnish. Electroplating silver with rhodium prevents this discoloration. Silver itself does not react with dilute nonoxidizing acids (hydrochloric or sulfuric acids) or strong bases (sodium hydroxide). However, oxidizing acids (nitric or concentrated sulfuric acids) dissolve it by reaction to form the unipositive silver ion, Ag⁺. The Ag⁺ ion is colorless, but a number of silver compounds are colored because of the influence of their other constituents.

Silver is almost always monovalent in its compounds, but an oxide, fluoride, and sulfide of divalent silver are known. Some coordination compounds of silver, also called silver complexes, contain divalent and trivalent silver. Although silver does not oxidize when heated, it can be oxidized chemically or electrolytically to form silver oxide or peroxide, a strong oxidizing agent. Because of this activity, silver finds considerable use as an oxidation catalyst in the production of certain organic materials.

Soluble silver salts, especially AgNO₃, have proved lethal in doses as small as 0.07 oz (2 g). Silver compounds may be slowly absorbed by the body tissues, with a resulting bluish or blackish pigmentation of the skin (argyria).

Silver is a rather rare element, ranking 63rd in order of abundance. Sometimes it occurs in nature as the free element (native silver) or alloyed with other metals. For the most part, however, silver is found in ores containing silver compounds. The principal silver ores are argentite, Ag₂S, cerargyrite or horn silver, AgCl, and several minerals in which silver sulfide is combined with sulfides of other metals; stephanite, 5Ag₂SÖSb₂S₅; polybasite, 9(Cu₂S, Ag₂S)Ö(Sb₂S₃, As₂S₃); proustite, 3Ag₂SÖAs₂S₃; and pyragyrite, 3Ag₂SÖSb₂S₃. About three-fourths of the silver produced is a by-product of the extraction of other metals, copper and lead in particular.

Pure silver is a white, moderately soft metal (2.5–3 on Mohs hardness scale), somewhat harder than gold. When polished, it has a brilliant luster and reflects 95% of the light falling on it. Silver is second to gold in malleability and ductility. Its density is 10.5 times that of water. The quality of silver, its fineness, is expressed as parts of pure silver per 1000 parts of total metal. Commercial silver is usually 999 fine. Silver is available commercially as sterling silver (7.5% copper) and in ingots, plate, moss, sheets, wire, castings, tubes, and powder.

Silver, with the highest thermal and electrical conductivities of all the metals, is used for electrical and electronic contact points and sometimes for special wiring. Silver has well-known uses in jewelry and silverware. Silver compounds are used in many photographic materials. In most of its uses, silver is alloyed with one or more other metals. Alloys in which silver is an ingredient include dental amalgam and metals for engine pistons and bearings.

An element commonly used in jewelry, coins, electronics, and photography. Silver has the highest electrical conductivity of any metal.

Investopedia Says:
Silver is considered to be a precious metal.

Not of interest in foods apart from its use in covering non-pareils, the silver beads used to decorate confectionery. Present in traces in all plant and animal tissues but not known to be a dietary essential, and has no known function, nor is enough ever absorbed to cause toxicity. See also oligodynamic.

Idioms beginning with silver:
silver lining

In addition to the idiom beginning with silver, also see born with a silver spoon; cross someone's palm with silver; hand to on a silver platter.

A whitish precious metal occurring mainly as a sulfide. Its atomic number is 47, and its atomic weight is 107.88. It is quite soft and is usually alloyed with small amounts of copper to increase its durability. It is used extensively in photography, radiography, and dentistry.

(click to enlarge)
Dendritic (branching) silver from Ontario (credit: Courtesy of Joseph and Helen Guetterman Collection; photograph, John H. Gerard)

Metallic chemical element, one of the transition elements, chemical symbol Ag, atomic number 47. It is a white, lustrous precious metal, valued for its beauty. It is also valued for its electrical conductivity, which is the highest of any metal. Between copper and gold in their common group of the periodic table, it is intermediate between them in many properties. Widely distributed in nature in small amounts, as the native metal and in ores, it is usually recovered as a by-product of copper and lead production. Its use in bullion and coins was overtaken in the 1960s by demand for industrial purposes, especially photography. It is also used in printed electrical circuits, electronic conductors, and contacts. It is the catalyst for converting ethylene to ethylene oxide, the precursor of many organic chemicals. Its use in alloys in sterling (92.5% silver, 7.5% copper) and plated silverware, ornaments, and jewelry remains important; yellow gold used in jewelry is typically 25% silver, and gold dental alloys are about 10% silver. Silver dental fillings are an amalgam of silver and mercury. Silver in compounds, the most important of which is silver nitrate, has valence 1. Its chloride, bromide, and iodide are used in photography and its iodide in cloud seeding.

For more information on silver, visit Britannica.com.

Silver coins are mentioned in many different contexts. It is not clear how much intrinsic power ascribed to the metal itself—some, no doubt, since there is evidence that in Suffolk around 1850 people with fits would beg twelve small silver items such as broken spoons or buckles, to melt into a curative ring, and in some of the stories where a hare (really a witch) is shot with a silver bullet, this is said to be made from a button. However, silver objects were not regularly thought powerful in the way that domestic iron objects were.

A silver sixpence is frequently mentioned: as a gift to a new baby; as a gift left by fairies for diligent servant girls, or for children shedding a tooth; as a lucky charm, especially in a bride's shoe; as a countercharm against witchcraft when churning milk. A particular healing power was ascribed to rings made from a silver coin which had been put into the collection in church (so-called ‘sacrament money’), usually a shilling or half a crown; to get it, the sufferer had to beg a penny apiece from twelve (or 30) different people, usually with the further condition that they must be unmarried, and of the sex opposite to the sufferer's, and then exchange them for the ‘sacrament money’. They were supposed to cure fits. Sometimes, it was thought sufficient to beg five, seven, or nine sixpenny or threepenny pieces from persons of the opposite sex, and make the ring of them.

Bibliography
The full bibliography list is available here.

• Opie and Tatem, 1989: 327-8, 357-8

Environment

In ore veins.

In cubic or octahedral crystals, but either is uncommon; more often it forms long contorted wires. However, the cubic Kongsberg (Norway) crystals--among the best--may be pseudomorphs formed from the sulfide mineral argentite (acanthite at room temperature).

Fresh surface bright white, usually blackened by tarnish. Luster metallic; hardness 2Ɖ-3; specific gravity 10.0-11.0. Very malleable and ductile.

Silver, usually fairly pure.

Pure silver fuses readily on charcoal to a white button. Impurities tend to make melting more difficult. Dissolves in nitric acid, producing a white curdy precipitate on the addition of hydrochloric acid.

No other white malleable metal, soluble in acid, is likely to be encountered in its native state. Lead is softer and grayer; platinum is harder and insoluble; the silvery sulfides are brittle.

In Mexico and Norway in veins with calcite and silver sulfides; often in wires and in good crystals. In n. Canada (Great Bear Lake) and Czechoslovakia with uranium ores (pitchblende). In Michigan in pure masses appended to copper sheets and forming aggregates known as "half-breeds." Native silver is not an important source of silver; lead and silver minerals with which it is commonly associated, as at Cobalt, Ontario, and in Idaho, are richer in silver. Lead ores that formed at higher temperatures than the sedimentary deposits of the Mississippi Valley are more likely to contain significant percentages of silver.

1. a chemical element, atomic number 47, atomic weight 107.870, symbol Ag. It is used in medicine for its caustic, astringent and antiseptic effects. Experimental poisoning with silver salts causes myopathy.
2. a coat color in dogs, foxes.

• s. amalgam — see amalgam.
• s. collie syndrome — see canine cyclic hematopoiesis.
• s. grass — aristida contorta.
• s. halide — any of the silver salts with halogens including bromine, chlorine, iodine used in photographic emulsion.
• s. iodide — soluble silver salt used in cloud seeding but presents no toxicological risk to local grazing cattle.
• s.-leaf ironbark — eucalyptus melanophloia.
• s.-leafed nightshade — solanum elaeagnifolium.
• s. nitrate — colorless or white crystals, used as a caustic and local anti-infective.
• s. nitrate (toughened) — a mixture of silver nitrate with hydrochloric acid, sodium chloride or potassium nitrate, occurring as white crystalline masses molded into pencils or cones, called caustic pencils; a convenient means of applying silver nitrate locally. Called also lunar caustic.
• s. protein — silver made colloidal by the presence of, or combination with, protein; an active germicide with a local irritant and astringent effect.
• s. stain — a method of demonstrating flagella on bacteria, or for visualizing very thin bacteria, such as leptospires.
• s. sulfadiazine — the silver salt of sulfadiazine, having bactericidal activity against many gram-positive and gram-negative organisms, as well as being effective against yeasts; used as a topical anti-infective for the prevention and treatment of wound sepsis in patients with second and third degree burns.
• s. weed — see potentilla anserina.

Silver is a precious metal associated with the emotions, the feminine quality, and the moon.

This article is about the chemical element. For the color, see Silver (color). For other uses, see Silver (disambiguation).

47 palladium ← silver → cadmium Cu ↑ Ag ↓ Au Periodic Table - Extended Periodic Table
General
Name, Symbol, Number	silver, Ag, 47
Element category	transition metals
Group, Period, Block	11, 5, d
Appearance	lustrous white metal
Standard atomic weight	107.8682(2)  g·mol−1
Electron configuration	[Kr] 4d10 5s1
Electrons per shell	2, 8, 18, 18, 1
Physical properties
Color	silver
Phase	solid
Density (near r.t.)	10.49  g·cm−3
Liquid density at m.p.	9.320  g·cm−3
Melting point	1234.93 K (961.78 °C, 1763.2 °F)
Boiling point	2435 K (2162 °C, 3924 °F)
Heat of fusion	11.28  kJ·mol−1
Heat of vaporization	250.58  kJ·mol−1
Specific heat capacity	(25 °C) 25.350  J·mol−1·K−1
Vapor pressure P(Pa) 1 10 100 1 k 10 k 100 k at T(K) 1283 1413 1575 1782 2055 2433
Atomic properties
Crystal structure	face-centered cubic
Oxidation states	1, 2, 3 (amphoteric oxide)
Electronegativity	1.93 (Pauling scale)
Ionization energies	1st: 731.0 kJ/mol
	2nd: 2070 kJ/mol
	3rd: 3361 kJ/mol
Atomic radius	144 pm
Covalent radius	145±5 pm
Van der Waals radius	172 pm
Miscellaneous
Magnetic ordering	diamagnetic
Electrical resistivity	(20 °C) 15.87 n Ω·m
Thermal conductivity	(300 K) 429  W·m−1·K−1
Thermal diffusivity	(300 K) 174 mm²/s
Thermal expansion	(25 °C) 18.9  µm·m−1·K−1
Speed of sound (thin rod)	(r.t.) 2680  m·s−1
Young's modulus	83  GPa
Shear modulus	30  GPa
Bulk modulus	100  GPa
Poisson ratio	0.37
Mohs hardness	2.5
Vickers hardness	251  MPa
Brinell hardness	24.5  MPa
CAS registry number	7440-22-4
Most-stable isotopes
Main article: Isotopes of silver iso NA half-life DM DE (MeV) DP 105Ag syn 41.2 d ε - 105Pd γ 0.344, 0.280, 0.644, 0.443 - 106mAg syn 8.28 d ε - 106Pd γ 0.511, 0.717, 1.045, 0.450 - 107Ag 51.839% 107Ag is stable with 60 neutrons 108mAg syn 418 y ε - 108Pd IT 0.109 108Ag γ 0.433, 0.614, 0.722 - 109Ag 48.161% 109Ag is stable with 62 neutrons 111Ag syn 7.45 d β− 1.036, 0.694 111Cd γ 0.342 -
References

Silver is a chemical element with the chemical symbol Ag (Latin: argentum, from the Ancient Greek: ἀργήεντος - argēentos, gen. of ἀργήεις - argēeis, "white, shining" ) and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal. The metal occurs naturally in its pure, free form (native silver), as an alloy with gold (electrum) and other metals, and in minerals such as argentite and chlorargyrite. Most silver is produced as a by-product of copper, gold, lead, and zinc refining.

Silver has been known since ancient times and has long been valued as a precious metal, used to make ornaments, jewelry, high-value tableware, utensils (hence the term silverware), and currency coins. Today, silver metal is used in electrical contacts and conductors, in mirrors and in catalysis of chemical reactions. Its compounds are used in photographic film and dilute solutions of silver nitrate and other silver compounds are used as disinfectants. Although the antimicrobial uses of silver have largely been supplanted by the use of antibiotics, further research into its clinical potential is in progress.

Contents 1 Characteristics 2 Isotopes 3 Silver compounds 4 Applications 4.1 Precious metal 4.2 Dentistry 4.3 Photography and electronics 4.4 Solder and brazing 4.5 Mirrors and optics 4.6 Nuclear reactors 4.7 Catalyst 4.8 Currency 4.9 Medicine 4.9.1 Medication 4.10 Food 4.11 Clothing 4.12 Silversmithery 5 History 6 Occurrence and extraction 7 Price 8 Precautions 9 See also 10 References 11 External links

Characteristics

Silver 1000oz bullion bar

Silver is a very ductile and malleable (slightly harder than gold) monovalent coinage metal with a brilliant white metallic luster that can take a high degree of polish. It has the highest electrical conductivity of all metals, even higher than copper, but its greater cost and tarnishability have prevented it from being widely used in place of copper for electrical purposes, though 13540 tons were used in the electromagnets used for enriching uranium during World War II (mainly because of the wartime shortage of copper).^[1][2] Another notable exception is in high-end audio cables.^[3]

Among metals, pure silver has the highest thermal conductivity^[4] (the non-metal diamond and superfluid helium II are higher), the whitest color, and the highest optical reflectivity^[5] (although aluminium slightly outdoes it in parts of the visible spectrum, and it is a poor reflector of ultraviolet light). Silver also has the lowest contact resistance of any metal. Silver halides are photosensitive and are remarkable for their ability to record a latent image that can later be developed chemically. Silver is stable in pure air and water, but tarnishes when it is exposed to air or water containing ozone or hydrogen sulfide to form a black layer of silver sulfide which can be cleaned off with dilute hydrochloric acid.^[6] The most common oxidation state of silver is +1 (for example, silver nitrate: AgNO₃); in addition, +2 compounds (for example, silver(II) fluoride: AgF₂) and +3 compounds (for example, potassium tetrafluoroargentate: K[AgF₄]) are known.

Isotopes

Main article: isotopes of silver

Naturally occurring silver is composed of two stable isotopes, ¹⁰⁷Ag and ¹⁰⁹Ag, with ¹⁰⁷Ag being the most abundant (51.839% natural abundance). Silver's standard atomic mass is 107.8682(2) u. Twenty-eight radioisotopes have been characterized, the most stable being ¹⁰⁵Ag with a half-life of 41.29 days, ¹¹¹Ag with a half-life of 7.45 days, and ¹¹²Ag with a half-life of 3.13 hours.

All of the remaining radioactive isotopes have half-lives that are less than an hour, and the majority of these have half-lives that are less than 3 minutes. This element has numerous meta states, the most stable being ^108mAg (t_* 418 years), ^110mAg (t_* 249.79 days) and ^106mAg (t_* 8.28 days).

Isotopes of silver range in atomic weight from 93.943 u (⁹⁴Ag) to 123.929 u (¹²⁴Ag). The primary decay mode before the most abundant stable isotope, ¹⁰⁷Ag, is electron capture and the primary mode after is beta decay. The primary decay products before ¹⁰⁷Ag are palladium (element 46) isotopes, and the primary products after are cadmium (element 48) isotopes.

The palladium isotope ¹⁰⁷Pd decays by beta emission to ¹⁰⁷Ag with a half-life of 6.5 million years. Iron meteorites are the only objects with a high-enough palladium-to-silver ratio to yield measurable variations in ¹⁰⁷Ag abundance. Radiogenic ¹⁰⁷Ag was first discovered in the Santa Clara meteorite in 1978.^[7] The discoverers suggest that the coalescence and differentiation of iron-cored small planets may have occurred 10 million years after a nucleosynthetic event. ¹⁰⁷Pd–¹⁰⁷Ag 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.^[8]

Silver compounds

Cessna 210 equipped with a silver iodide generator for cloud seeding

Silver metal dissolves readily in nitric acid (HNO₃) to produce silver nitrate (AgNO₃), a transparent crystalline solid that is photosensitive and readily soluble in water. Silver nitrate is used as the starting point for the synthesis of many other silver compounds, as an antiseptic, and as a yellow stain for glass in stained glass. Silver metal does not react with sulfuric acid, which is used in jewellery-making to clean and remove copper oxide firescale from silver articles after silver soldering or annealing. However, silver reacts readily with sulfur or hydrogen sulfide H₂S to produce silver sulfide, a dark-coloured compound familiar as the tarnish on silver coins and other objects. Silver sulfide also forms silver whiskers when silver electrical contacts are used in an atmosphere rich in hydrogen sulfide.

Silver bromide is a yellow, low hardness salt.

Silver chloride (AgCl) is precipitated from solutions of silver nitrate in the presence of chloride ions, and the other silver halides used in the manufacture of photographic emulsions are made in the same way using bromide or iodide salts. Silver chloride is used in glass electrodes for pH testing and potentiometric measurement, and as a transparent cement for glass. Silver iodide has been used in attempts to seed clouds to produce rain.^[6]

Silver oxide (Ag₂O) produced when silver nitrate solutions are treated with a base, is used as a positive electrode (cathode) in watch (battery) batteries. Silver carbonate (Ag₂CO₃) is precipitated when silver nitrate is treated with sodium carbonate (Na₂CO₃).^[9]

Silver fulminate (AgONC), a powerful, touch-sensitive explosive used in percussion caps, is made by reaction of silver metal with nitric acid in the presence of ethanol (C₂H₅OH). Another dangerously explosive silver compound is silver azide (AgN₃), formed by reaction of silver nitrate with sodium azide (NaN₃).^[10]

Latent images formed in silver halide crystals are developed by treatment with alkaline solutions of reducing agents such as hydroquinone, metol (4-(methylamino)phenol sulfate) or ascorbate which reduce the exposed halide to silver metal. Alkaline solutions of silver nitrate can be reduced to silver metal by reducing sugars such as glucose, and this reaction is used to silver glass mirrors and the interior of glass Christmas ornaments. Silver halides are soluble in solutions of sodium thiosulfate (Na₂S₂O₃) which is used as a photographic fixer, to remove excess silver halide from photographic emulsions after image development.^[9]

Silver metal is attacked by strong oxidizers such as potassium permanganate (KMnO₄) and potassium dichromate (K₂Cr₂O₇), and in the presence of potassium bromide (KBr), these compounds are used in photography to bleach silver images, converting them to silver halides that can either be fixed with thiosulfate or re-developed 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.^[9]

Applications

Precious metal

Goddess Minerva on a Roman silver plate, 1st century BCE

A major use of silver is as a precious metal, and it has long been used for making high-value objects reflecting the wealth and status of the owner.

Jewellery and silverware are traditionally made from sterling silver (standard silver), an alloy of 92.5% silver with 7.5% copper. In the United States, only an alloy consisting of at least 92.5% fine silver can be marketed as "silver". Sterling silver is harder than pure silver, and has a lower melting point (893 °C) than either pure silver or pure copper.^[6] Britannia silver is an alternative hallmark-quality standard containing 95.8% silver, often used to make silver tableware and wrought plate. With the addition of germanium, the patented modified alloy Argentium Sterling Silver is formed, with improved properties including resistance to firescale.

Sterling silver jewelry is often plated with a thin coat of .999 fine silver to give the item a shiny finish. This process is called "flashing". Silver jewelry can also be plated with rhodium (for a bright, shiny look) or gold.

Silver is a constituent of almost all colored carat gold alloys and carat gold solders, giving the alloys paler colour and greater hardness.^[11] White 9 carat gold contains 62.5% silver and 37.5% gold, while 22 carat gold contains up to 8.4% silver or 8.4% copper.^[11]

Silver is used in medals, denoting second place. Some high-end musical instruments are made from sterling silver, such as the flute.

Dentistry

Silver can be alloyed with mercury, tin and other metals at room temperature to make amalgams that are widely used for dental fillings. To make dental amalgam, a mixture of powdered silver and other metals is mixed with mercury to make a stiff paste that can be adapted to the shape of a cavity. The dental amalgam achieves initial hardness within minutes but sets hard in a few hours.

Photography and electronics

Photography used 30.98% of the silver consumed in 1998 in the form of silver nitrate and silver halides, and in 2001, 23.47% for photography, while 20.03% was used in jewelry, 38.51% for industrial uses, and only 3.5% for coins and medals. The use of silver in photography has rapidly declined, due to the lower demand for consumer colour film from the advent of digital technology, since in 2007 of the 894.5 million ounces of silver in supply, just 128.3 million ounces (14.3%) were consumed by the photographic sector, and the total amount of silver consumed in 2007 by the photographic sector compared to 1998 is just 50%.^[12]

Some electrical and electronic products use silver for its superior conductivity, even when tarnished. For example, printed circuits are made using silver paints,^[6] and computer keyboards use silver electrical contacts. Some high-end audio hardware (DACs, preamplifiers, etc.) are fully silver-wired, which is believed to cause the least loss of quality in the signal. Silver cadmium oxide is used in high voltage contacts because it can withstand arcing.

During World War II the short supply of copper brought about the government's use of silver from the Treasury vaults for conductors at Oak Ridge National Laboratory. (After the war ended the silver was returned to the vaults.)^[13]

Solder and brazing

Silver is used to make solder and brazing alloys, electrical contacts, and high-capacity silver-zinc and silver-cadmium batteries. Silver in a thin layer on top of a bearing material can provide a significant increase in galling resistance and reduce wear under heavy load, particularly against steel.

Mirrors and optics

Mirrors which need superior reflectivity for visible light are made with silver as the reflecting material in a process called silvering, though common mirrors are backed with aluminium. Using a process called sputtering, silver (and sometimes gold) can be applied to glass at various thicknesses, allowing different amounts of light to penetrate. Silver is usually reserved for coatings of specialized optics, and the silvering most often seen in architectural glass and tinted windows on vehicles is produced by sputtered aluminium, which is cheaper and less susceptible to tarnishing and corrosion.^[14]

Nuclear reactors

Because silver readily absorbs free neutrons, it is commonly used to make control rods that regulate the fission chain reaction in pressurized water nuclear reactors, generally in the form of an alloy containing 80% silver, 15% indium, and 5% cadmium.

Catalyst

Silver's catalytic properties make it ideal for use as a catalyst in oxidation reactions, for example, the production of formaldehyde from methanol and air by means of silver screens or crystallites containing a minimum 99.95 weight-percent silver. Silver (upon some suitable support) is probably the only catalyst available today to convert ethylene to ethylene oxide (later hydrolyzed to ethylene glycol, used for making polyesters)—a very important industrial reaction.

Oxygen dissolves in silver relatively easily compared to other gases present in air. Attempts have been made to construct silver membranes of only a few monolayers thickness. Such a membrane could be used to filter pure oxygen from air and water.

Currency

Main articles: Silver coin and Silver standard

Silver, in the form of electrum (a gold-silver alloy), was coined to produce money in around 700 BCE by the Lydians. Later, silver was refined and coined in its pure form. Many nations used silver as the basic unit of monetary value. The words for "silver" and "money" are the same in at least 14 languages. In the modern world, silver bullion has the ISO currency code XAG. The name of the United Kingdom monetary unit "pound" reflects the fact that it originally represented the value of one troy pound of sterling silver. In the 1800s, many nations, such as the United States and Great Britain, switched from silver to a gold standard of monetary value, then in the 20th century to fiat currency.

Medicine

Handforged silver wine goblets. Usage of silverware was encouraged by the antibiotic action of silver

Silver ions and silver compounds show a toxic effect on some bacteria, viruses, algae and fungi, typical for heavy metals like lead or mercury, but without the high toxicity to humans that are normally associated with these other metals. Its germicidal effects kill many microbial organisms in vitro, but testing and standardization of silver products is difficult.^[15]

Hippocrates, the father of modern medicine, wrote that silver had beneficial healing and anti-disease properties, and the Phoenicians used to store water, wine, and vinegar in silver bottles to prevent spoiling. In the early 1900s people would put silver dollars in milk bottles to prolong the milk's freshness.^[16] Its germicidal effects increase its value in utensils and as jewellery. The exact process of silver's germicidal effect is still not well understood, although theories exist. One of these is the oligodynamic effect, which explains the effect on microorganisms but would not explain antiviral effects.

Silver compounds were used to prevent infection in World War I before the advent of antibiotics. Silver nitrate solution was a standard of care but was largely replaced by silver sulfadiazine cream (SSD Cream),^[17] which was generally the "standard of care" for the antibacterial and antibiotic treatment of serious burns until the late 1990s.^[18] Now, other options, such as silver-coated dressings (activated silver dressings), are used in addition to SSD cream. However, the evidence for the effectiveness of such silver-treated dressings is mixed and although the evidence is promising it is marred by the poor quality of the trials used to assess these products.^[19] Consequently a major systematic review by the Cochrane Collaboration found insufficient evidence to recommend the use of silver-treated dressings to treat infected wounds.^[19]

The widespread use of silver went out of fashion with the development of modern antibiotics. However, recently there has been renewed interest in silver as a broad-spectrum antimicrobial. In particular, silver is being used with alginate, a naturally occurring biopolymer derived from seaweed, in a range of products designed to prevent infections as part of wound management procedures, particularly applicable to burn victims.^[20] In 2007, AGC Flat Glass Europe introduced the first antibacterial glass to fight hospital-caught infection: it is covered with a thin layer of silver.^[21] In addition, Samsung has introduced washing machines with a final rinse containing silver ions to provide several days of antibacterial protection in the clothes.^[22] Kohler has introduced a line of toilet seats that have silver ions embedded to kill germs. A company called Thomson Research Associates has begun treating products with Ultra Fresh, an anti-microbial technology involving "proprietary nano-technology to produce the ultra-fine silver particles essential to ease of application and long-term protection."^[23] The U.S. Food and Drug Administration (FDA) has recently approved an endotracheal breathing tube with a fine coat of silver for use in mechanical ventilation, after studies found it reduced the risk of ventilator-associated pneumonia.^[24]

It has long been known that antibacterial action of silver is enhanced by the presence of an electric field. Applying a few volts of electricity across silver electrodes drastically enhances the rate that bacteria in solution are killed. It was found recently that the antibacterial action of silver electrodes is greatly improved if the electrodes are covered with silver nanorods.^[25]

Medication

Today, various kinds of silver compounds, or devices to make solutions or colloids containing silver, are sold as remedies for a wide variety of diseases. Although most colloidal silver preparations are harmless, some people using these home-made solutions excessively have developed argyria over a period of months or years.^[26] High doses of colloidal silver can result in coma, pleural edema, and hemolysis.^[27]

Silver is widely used in topical gels and impregnated into bandages because of its wide-spectrum antimicrobial activity. The anti-microbial properties of silver stem from the chemical properties of its ionized form, Ag⁺. This ion forms strong molecular bonds with other substances used by bacteria to respire, such as molecules containing sulfur, nitrogen, and oxygen.^[28] Once the Ag⁺ ion complexes with these molecules, they are rendered unusable by the bacteria, depriving it of necessary compounds and eventually leading to the bacteria's death.

Food

In India and Pakistan, foods, especially sweets, can be found decorated with a thin layer of silver known as vark. Silver as a food additive is given the E number E174 and is classed as a food coloring. It is used solely for external decoration, such as on chocolate confectionery, in the covering of dragées and the decoration of sugar-coated flour confectionery. In Australia, it is banned as a food additive.

Clothing

Silver inhibits the growth of bacteria and fungi. It keeps odor to a minimum and reduces the risk of bacterial and fungal infection. In clothing, the combination of silver and moisture movement (wicking) may help to reduce the harmful effects of prolonged use in active and humid conditions.

Silver is used in clothing in two main forms:

• A form in which silver ions are integrated into the polymer from which yarns are made (a form of nanotechnology)
• A form in which the silver is coated onto the yarns.

In both cases the silver prevents the growth of a broad spectrum of bacteria and fungi.

Recorded use of silver to prevent infection dates to ancient Greece and Rome, it was rediscovered in the Middle Ages, where it was used for several purposes, such as to disinfect water and food during storage, and also for the treatment of burns and wounds as wound dressing. In the 19th century, sailors on long ocean voyages would put silver coins in barrels of water and wine to keep the liquid pure. Pioneers in America used the same idea as they made their journey from coast to coast. Silver solutions were approved in the 1920s by the US Food and Drug Administration for use as antibacterial agents. Today, wound dressings containing silver are well established for clinical wound care and have recently been introduced in consumer products such as sticking plasters.^[29]

Silversmithery

Main article: Silversmithery

Band made of Silver.

Historically the training and guild organization of goldsmiths included silversmiths as well, and the two crafts remain largely overlapping. Unlike blacksmiths, silversmiths do not shape the metal while it is red-hot but instead, work it at room temperature with gentle and carefully placed hammerblows. The essence of silversmithing is to take a flat piece of metal and by means of different hammers, stakes and other simple tools, to transform it into a useful object.^[30]

While silversmiths specialize in, and principally work, silver, they also work with other metals such as gold, copper, steel, and brass. They make jewellery, silverware, armour, vases, and other artistic items. Because silver is such a malleable metal, silversmiths have a large range of choices with how they prefer to work the metal. Historically, silversmiths are mostly referred to as goldsmiths, which was usually the same guild. In the western Canadian silversmith tradition, guilds do not exist; however, mentoring through colleagues becomes a method of professional learning within a community of craftspeople ^[31].

Silver is cheaper than gold, though still valuable, and so is very popular with jewellers who are just starting out and cannot afford to make pieces in gold, or as a practicing material for goldsmith apprentices. Silver has also become very fashionable, and is used frequently in more artistic jewellery pieces.

Traditionally silversmiths mostly made "silverware" (cutlery, table flatware, bowls, candlesticks and such). Only in more recent times has silversmithing become mainly work in jewellery, as much less solid silver tableware is now handmade.

History

The symbol for the Moon has been used since ancient times to represent silver.

The word "silver" appears in Anglo-Saxon in various spellings such as seolfor and siolfor. A similar form is seen throughout the Teutonic languages (compare Old High German silabar and silbir). The chemical symbol Ag is from the Latin for "silver", argentum (compare Greek άργυρος, árgyros), from the Indo-European root *arg- meaning "white" or "shining". Silver has been known since ancient times. It is mentioned in the book of Genesis, and 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 using surface mining.^[6]

In the Gospels, Jesus' disciple Judas Iscariot is infamous for having taken a bribe of thirty coins of silver from religious leaders in Jerusalem to turn Jesus Christ over to the Romans.

Set aside certain circumstances^{[clarification needed]}, Islam permits Muslim men to wear silver jewelry. Muhammad himself wore a silver signet ring.

Occurrence and extraction

Main article: Silver mining

Silver ore with Lincoln cent for scale

Time trend of silver production

Silver is found in native form, alloyed with gold or combined with sulfur, arsenic, antimony or chlorine in ores such as argentite (Ag₂S), horn silver (AgCl), and pyrargyrite (Ag₃SbS₃). The principal sources of silver are the ores of copper, copper-nickel, lead, and lead-zinc obtained from Peru, Mexico, China, Australia, Chile, Poland and Kosovo.^[6] Peru and Mexico have been mining silver since 1546 and are still major world producers. Top silver-producing mines are Proaño / Fresnillo (Mexico), Cannington (Queensland, Australia), Dukat (Russia), Uchucchacua (Peru) and Greens Creek mine (Alaska).^[32]

The metal can also be produced during the electrolytic refining of copper and by the application of the Parkes process on lead metal obtained from lead ores that contain small amounts of silver. Commercial-grade fine silver is at least 99.9% pure silver, and purities greater than 99.999% are available. In 2007, Peru was the world's top producer of silver, closely followed by Mexico, according to the British Geological Survey.

Price

Main articles: Silver as an investment and Silver standard

Silver output in 2005

As of October 2008 silver is about 1/75th the price of gold by mass.^[33] Silver once traded at 1/6th to 1/12th the price of gold, prior to the Age of Discovery and the discovery of great silver deposits in the Americas, including Peru, Mexico and the United States, such as the vast Comstock Lode in Virginia City, Nevada, USA. This then resulted in the debate over cheap Free Silver to benefit the agricultural sector, which was among the most prolonged and difficult in that country's history^{[clarification needed]} and dominated public discourse during the latter decades of the nineteenth century.

Over the last 100 years the price of silver and the gold/silver price ratio have fluctuated greatly due to competing industrial and store-of-value demands. In 1980 the silver price rose to an all-time high of US$49.45 per troy ounce. By December 2001 the price had dropped to US$4.15 per ounce, and in May 2006 it had risen back as high as US$15.21 per ounce. In March 2008 silver reached US$21.34 per ounce.^[34]

The price of silver is important in Judaic Law. The lowest fiscal amount that a Jewish court, or Beth Din, can convene to adjudicate a case over is a shova pruta (value of a Babylonian pruta coin). This is fixed at 1/8 of a gram of pure, unrefined silver, at market price.

Precautions

Silver plays no known natural biological role in humans, and possible health effects of silver are a subject of dispute. Silver itself is not toxic but most silver salts are, and some may be carcinogenic. Silver and compounds containing silver (like colloidal silver) can be absorbed into the circulatory system and become deposited in various body tissues leading to a condition called argyria which results in a blue-grayish pigmentation of the skin, eyes, and mucous membranes. Although this condition does not otherwise harm a person's health, it is disfiguring and usually permanent. Argyria is rare, and mild forms are sometimes mistaken for cyanosis.^[6]

See also

• List of Silver Compounds
• Silverpoint drawing

References

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2. ^ "Eastman at Oak Ridge - Dr. Howard Young". http://www.tnengineering.net/AICHE/eastman-oakridge-young.htm. Retrieved on 2009-06-06. 
3. ^ Oman, H. (1992). "Not invented here? Check your history". Aerospace and Electronic Systems Magazine 7 (1): 51–53. doi:10.1109/62.127132. 
4. ^ "WebElements Periodic Table of the Elements | Silver | Essential information". Webelements.com. http://www.webelements.com/silver/. Retrieved on 2009-04-05. 
5. ^ Edwards, H.W. & Petersen, R.P. (1936). "Reflectivity of evaporated silver films". Phys. Rev. 9: 871. 
6. ^ ^{a b c d e f g} C. R. Hammond (2000). The Elements, in Handbook of Chemistry and Physics 81th edition. CRC press. ISBN 0849304814. 
7. ^ Kelly, William R. (1978). "Evidence for the existence of ¹⁰⁷Pd in the early solar system". Geophysical Research Letters 5: 1079. doi:10.1029/GL005i012p01079. 
8. ^ Russell, Sara S.; Gounelle, Matthieu; Hutchison, Robert (2001 pages = 1991–2004). "Origin of Short-Lived Radionuclides". Philosophical Transactions: Mathematical, Physical and Engineering Sciences 359 (1787). doi:10.2307/3066270 (inactive 2009-05-30). http://www.jstor.org/stable/3066270. 
9. ^ ^{a b c} Hans I. Bjelkhagen (1995). Silver-halide recording materials: for holography and their processing. Springer. p. 156-166. ISBN 3540586199. 
10. ^ Rudolf Meyer, Josef Köhler, Axel Homburg (2007). Explosives. Wiley-VCH. p. 284. ISBN 3527316566. http://books.google.com/books?id=ATiYCfo1VcEC&pg=PA284&dq=%22silver++fulminate%22&lr=&num=100&as_brr=3. 
11. ^ ^{a b} "Gold Jewellery Alloys > Utilise Gold. Scientific, industrial and medical applications, products ,suppliers from the World Gold Council". Utilisegold.com. 2000-01-20. http://www.utilisegold.com/jewellery_technology/colours/colour_alloys/. Retrieved on 2009-04-05. 
12. ^ "Silver Supply & Demand". The Silver Institute. http://www.silverinstitute.org/supply_demand.php. Retrieved on 2009-05-05. 
13. ^ Isaac Asimov. Building Blocks of the Universe. 
14. ^ Ray N. Wilson (2004). Reflecting Telescope Optics: Basic design theory and its historical development. Springer. p. 422. ISBN 3540401067. http://books.google.com/books?id=isH9fTnpc7YC&lpg=PA429&dq=silver%20optics&lr=&as_drrb_is=q&as_minm_is=0&as_miny_is=&as_maxm_is=0&as_maxy_is=&num=100&as_brr=3&pg=PA429. 
15. ^ Chopra I (April 2007). "The increasing use of silver-based products as antimicrobial agents: a useful development or a cause for concern?". The Journal of antimicrobial chemotherapy 59 (4): 587–90. doi:10.1093/jac/dkm006. PMID 17307768. 
16. ^ "Antibacterial effects of silver". http://www.saltlakemetals.com/Silver_Antibacterial.htm. 
17. ^ Chang TW, Weinstein L (December 1975). "Prevention of herpes keratoconjunctivitis in rabbits by silver sulfadiazine". Antimicrob. Agents Chemother. 8 (6): 677–8. PMID 1211919. PMC: 429446. http://aac.asm.org/cgi/pmidlookup?view=long&pmid=1211919. 
18. ^ Atiyeh BS, Costagliola M, Hayek SN, Dibo SA (March 2007). "Effect of silver on burn wound infection control and healing: review of the literature". Burns : journal of the International Society for Burn Injuries 33 (2): 139–48. doi:10.1016/j.burns.2006.06.010. PMID 17137719. 
19. ^ ^{a b} Lo SF, Hayter M, Chang CJ, Hu WY, Lee LL (August 2008). "A systematic review of silver-releasing dressings in the management of infected chronic wounds". Journal of clinical nursing 17 (15): 1973–85. doi:10.1111/j.1365-2702.2007.02264.x. PMID 18705778. 
20. ^ Hermans MH (December 2006). "Silver-containing dressings and the need for evidence". The American journal of nursing 106 (12): 60–8; quiz 68–9. PMID 17133010. 
21. ^ "AGC Flat Glass Europe launches world’s first antibacterial glass". 2007-09-04. http://www.agc-flatglass.eu/AGC+Flat+Glass+Europe/English/Homepage/News/Press+room/Press-Detail-Page/page.aspx/979?pressitemid=1031. 
22. ^ "Samsung laundry featuring SilverCare Technology". Samsung. Archived from the original on 2006-05-31. http://web.archive.org/web/20060531115914/http://www.samsung.com/PressCenter/PressRelease/PressRelease.asp?seq=20060213_0000233684. Retrieved on 2007-08-06. 
23. ^ ""Ultra-Fresh technology is based on the power of silver to fight bacteria"". Express Textile. http://www.expresstextile.com/20050731/perspectives01.shtml. 
24. ^ "FDA Clears Silver-Coated Breathing Tube For Marketing". 2007-11-08. http://www.fda.gov/bbs/topics/NEWS/2007/NEW01741.html. Retrieved on 2007-11-11. 
25. ^ O. Akhavan and E. Ghaderi (2009). "Enhancement of antibacterial properties of Ag nanorods by electric field". Sci. Technol. Adv. Mater. 10: 015003. doi:10.1088/1468-6996/10/1/015003. http://www.iop.org/EJ/article/1468-6996/10/1/015003/stam9_1_015003.pdf. 
26. ^ Fung MC, Bowen DL (1996). "Silver products for medical indications: risk-benefit assessment". Journal of toxicology. Clinical toxicology 34 (1): 119–26. doi:10.3109/15563659609020246. PMID 8632503. 
27. ^ Wadhera A, Fung M (2005). "Systemic argyria associated with ingestion of colloidal silver". Dermatology online journal 11 (1): 12. PMID 15748553. http://dermatology.cdlib.org/111/case_reports/argyria/wadhera.html. 
28. ^ Slawson RM, Van Dyke MI, Lee H, Trevors JT (January 1992). "Germanium and silver resistance, accumulation, and toxicity in microorganisms". Plasmid 27 (1): 72–9. doi:10.1016/0147-619X(92)90008-X. PMID 1741462. 
29. ^ "Silver in Textiles and Clothing". Americanelements.com. http://www.americanelements.com/agnp.html. Retrieved on 2009-04-05. 
30. ^ "Chambers Search Chambers". http://www.chambersharrap.co.uk/chambers/features/chref/chref.py/main?query=Silversmith&title=21st&sourceid=Mozilla-search. Retrieved on 2009-06-06. 
31. ^ Kelly McRae. "Trade Secrets". Western Horseman Magazine. http://westernhorseman.com/index.php?option=com_content&task=view&id=861&Itemid=79. Retrieved on 2009-06-06. 
32. ^ "Top silver producers". Infomine.com. http://www.infomine.com/commodities/silver.asp. Retrieved on 2009-04-05. 
33. ^ O’Connell, Rhona. "Gold:silver ratio will narrow, but base metals outlook ultra-gloomy – UBS". Mineweb.com. http://www.mineweb.com/mineweb/view/mineweb/en/page33?oid=71867&sn=Detail. Retrieved on 2008-11-13. 
34. ^ "Silver Cash daily plot". Barchart.com. http://charts3.barchart.com/chart.asp?sym=SIY0&data=A&jav=adv&vol=Y&evnt=adv&grid=Y&code=BSTK&org=stk&fix=. 

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• WebElements.com – Silver
• Society of American Silversmiths
• Silver Statistics and Information, USGS publications on the worldwide production of silver
• The Silver Institute A silver industry website
• A collection of silver items Samples of silver
• Transport, Fate and Effects of Silver in the Environment
• Picture in the Element collection from Heinrich Pniok

v • d • e Periodic table
H																															He
Li	Be																									B	C	N	O	F	Ne
Na	Mg																									Al	Si	P	S	Cl	Ar
K	Ca															Sc	Ti	V	Cr	Mn	Fe	Co	Ni	Cu	Zn	Ga	Ge	As	Se	Br	Kr
Rb	Sr															Y	Zr	Nb	Mo	Tc	Ru	Rh	Pd	Ag	Cd	In	Sn	Sb	Te	I	Xe
Cs	Ba	La	Ce	Pr	Nd	Pm	Sm	Eu	Gd	Tb	Dy	Ho	Er	Tm	Yb	Lu	Hf	Ta	W	Re	Os	Ir	Pt	Au	Hg	Tl	Pb	Bi	Po	At	Rn
Fr	Ra	Ac	Th	Pa	U	Np	Pu	Am	Cm	Bk	Cf	Es	Fm	Md	No	Lr	Rf	Db	Sg	Bh	Hs	Mt	Ds	Rg	Uub	Uut	Uuq	Uup	Uuh	Uus	Uuo
Alkali metals Alkaline earth metals Lanthanoids Actinoids Transition metals Other metals Metalloids Other nonmetals Halogens Noble gases

v • d • e   Silver compounds AgBF4 · AgBr · AgBrO3 · AgCN · AgCNO · AgCl · AgClO3 · AgClO4 · AgF · AgF2 · AgI · AgIO3 · AgNO3 · AgN3 · AgO · AgPF6 · Ag2CO3 · Ag2C2 · Ag2C2O4 · Ag2CrO4 · Ag2F · Ag2MoO4 · Ag2O · Ag2S · Ag2SO4 · Ag2Se · Ag2SeO3 · Ag2Te

v • d • e Jewellery materials Precious metals: Gold · Palladium · Platinum · Rhodium · Silver Precious metal alloys: Colored gold · Electrum · Platinum sterling · Sterling silver Base metals/alloys: Brass · Bronze · Copper · Stainless steel Mineral Gemstones: Aventurine · Agate · Alexandrite · Amethyst · Aquamarine · Carnelian · Citrine · Diamond · Emerald · Garnet · Jade · Jasper · Malachite · Lapis lazuli · Moonstone · Onyx · Opal · Peridot · Quartz · Ruby · Sapphire · Sodalite · Sunstone · Tanzanite · Tiger's Eye · Topaz Organic Gemstones: Amber · Copal · Coral · Jet · Pearl

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Dansk (Danish)
n. - sølv, sølvtøj, sølvpenge
v. tr. - forsølve, belægge
v. intr. - få sølvglans
adj. - sølvblank, sølvlignende, sølv-

idioms:

• silver birch    en art birketræ
• silver bullet    sølvkugle
• silver jubilee    sølvjubilæum
• silver medal    sølvmedalje
• silver paper    sølvpapir, folie
• silver plated    forsølvet
• silver screen    det hvide lærred
• silver tongue    veltalenhed, have ordet i sin magt
• silver wedding anniversary    sølvbryllupsdag

Nederlands (Dutch)
zilver, verzilveren

Français (French)
n. - argent, argenterie, couverts en argent, monnaie, médaille d'argent
v. tr. - argenter
v. intr. - argenter
adj. - d'argent, argenté

idioms:

• silver birch    bouleau argenté
• silver bullet    panacée
• silver jubilee    vingt-cinquième anniversaire
• silver medal    médaille d'argent
• silver paper    papier d'argent
• silver plate    métal argenté
• silver screen    le grand écran
• silver tongue    langue déliée
• silver wedding anniversary    noces d'argent

Deutsch (German)
n. - Silber
v. - versilbern, ergrauen (lassen)
adj. - silbern, Silber-

idioms:

• silver birch    (Bot.) Weißbirke
• silver bullet    magische Waffe, Zauberformel, Wunderlösung
• silver jubilee    silbernes Jubiläum
• silver medal    Silbermedaille
• silver paper    Silberpapier
• silver plate    Silberauflage, Silbergeschirr
• silver screen    Leinwand
• silver tongue    Redegewandtheit
• silver wedding anniversary    Silberhochzeit

Ελληνική (Greek)
n. - άργυρος, ασήμι, ασημικά, αργύρια
v. - επαργυρώνω, ασημοκαπνίζω
adj. - αργυρός, ασημένιος, αργυρούχος, ασημοκαπνίζω

idioms:

• silver birch    (φυτολ.) σημύδα η λευκή
• silver bullet    (καθομ.) μαγική λύση προβλήματος
• silver jubilee    25η επέτειος
• silver medal    αργυρό μετάλλιο
• silver paper    ασημόχαρτο, ευαισθητοποιημένο χαρτί
• silver plated    επάργυρος, ασημοκαπνισμένος
• silver screen    οθόνη του κινηματογράφου, (ο) κινηματογράφος
• silver tongue    γλυκύτητα λόγων
• silver wedding anniversary    25η επέτειος γάμων, αργυροί γάμοι

Italiano (Italian)
argentare, argenteo

idioms:

• silver birch    betulla bianca
• silver bullet    pallottola d'argento, treno rapido (USA)
• silver jubilee    nozze d'argento, 25o anniversario del regno
• silver medal    medaglia d'argento
• silver paper    carta argentata
• silver plate    argenteria placcata
• silver plated    placcato argento
• silver screen    il cinema
• silver tongue    eloquenza
• silver wedding    nozze d'argento

Português (Portuguese)
n. - prata (f), cor (f) de prata, baixela (f) de prata
v. - pratear, embranquecer, ficar grisalho
adj. - argênteo, prateado

idioms:

• silver birch    tipo de árvore (f)
• silver bullet    bala (f) de prata
• silver jubilee    jubileu (m) de prata
• silver medal    medalha (f) de prata
• silver paper    papel (m) prateado
• silver plated    prateado
• silver screen    tela (f) prateada para cinema
• silver tongue    eloquência (f)
• silver wedding    bodas (f pl) de prata

Русский (Russian)
серебро, серебряные монеты, серебряные изделия, серебряный, серебристый, мелодичный, покрывать серебром, амальгамировать, серебриться, седеть

idioms:

• silver birch    серебряная береза
• silver bullet    серебряная пуля
• silver jubilee    серебряный юбилей
• silver medal    серебряная медаль
• silver paper    белая папиросная бумага, фольга
• silver plated    посеребренный
• silver screen    киноэкран
• silver tongue    красноречие
• silver wedding    серебряная свадьба

Español (Spanish)
n. - plata, vajilla o cubiertos de plata, color de plata
v. tr. - platear, azogar, blanquear
v. intr. - volverse plateado
adj. - de plata, plateado, argentino

idioms:

• silver birch    abedul común
• silver bullet    varita mágica
• silver jubilee    vigésimo quinto aniversario
• silver medal    medalla de plata
• silver paper    papel de plata
• silver plate    baño de plata, vajilla de plata
• silver screen    industria del cine
• silver tongue    elocuencia
• silver wedding anniversary    bodas de plata

Svenska (Swedish)
n. - silver, silverpengar
v. - försilvra, bli försilvrad, försilvras
adj. - silver-, av silver

中文（简体）(Chinese (Simplified))
银, 银器, 银币, 镀银于, 使有银色光泽, 变成银色, 银的, 含银的, 镀银的, 银色的, 有银色光泽的

idioms:

• silver birch    白桦树
• silver bullet    银子弹
• silver jubilee    二十五周年纪念
• silver medal    银质奖章, 银牌
• silver paper    锡箔纸
• silver plated    包银的, 镀银的
• silver screen    银幕, 电影
• silver tongue    能言善辩, 口才好的
• silver wedding anniversary    银婚纪念, 结婚25周年纪念

中文（繁體）(Chinese (Traditional))
n. - 銀, 銀器, 銀幣
v. tr. - 鍍銀於, 使有銀色光澤
v. intr. - 變成銀色
adj. - 銀的, 含銀的, 鍍銀的, 銀色的, 有銀色光澤的

idioms:

• silver birch    白樺樹
• silver bullet    銀子彈
• silver jubilee    二十五周年紀念
• silver medal    銀質獎章, 銀牌
• silver paper    錫箔紙
• silver plated    包銀的, 鍍銀的
• silver screen    銀幕, 電影
• silver tongue    能言善辯, 口才好的
• silver wedding anniversary    銀婚紀念, 結婚25週年紀念

한국어 (Korean)
n. - 은(금속 원소), 은빛의 광택, 은화
v. tr. - 은을 씌우다, 백발이 되게 하다
v. intr. - 은빛이 되다, (머리가) 백발이 되다
adj. - 은의, 웅변의, (결혼 기념일 등) 25주년의

日本語 (Japanese)
n. - 銀, 銀細工品, 銀貨, 銀色
v. - 銀をかぶせる, 銀めっきする, 銀白色になる, 銀色に変わる
adj. - 銀の, 銀と化合した, 銀のような, 澄んだ

idioms:

• silver birch    シラカンバ
• silver bullet    ピストル
• silver jubilee    二十五周年祝典
• silver medal    銀メダル
• silver paper    銀器を包む薄紙, 銀紙
• silver plated    銀メッキの
• silver screen    銀幕, 映画界
• silver tongue    雄弁
• silver wedding    銀婚式
• silver wedding anniversary    銀婚式

العربيه (Arabic)
‏(الاسم) طبق فضي للمائدة, قطعه نقد فضيه, فضه (فعل) يطلي بالفضه, يفضض (صفه) فضي‏

עברית (Hebrew)
n. - ‮כסף (מתכת), מטבעות כסף, מצלצלים, כלי-כסף‬
v. tr. - ‮הכסיף (כיסה בצבע כסף)‬
v. intr. - ‮הכסיף, האפיר, הלבין (שיער)‬
adj. - ‮כספי, עשוי כסף, כסוף, מוכסף, צלול, מצלצל, שני במעלה‬

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