SILVER

Silver is a chemical element with the symbol Ag (Latin: argentum).

Silver has been known since antiquity. It has long been valued as a precious metal and used in currency, ornaments and jewelry, as well as utensils (hence the term silverware). Today, it is also used in photographic film, electrical contacts, and mirrors. Elemental silver is also used to catalyze chemical reactions.

Silver has certain antimicrobial activity. In the past, dilute solutions of silver nitrate were used as disinfectants, though this has been supplanted by other treatments. In alternative medicine, there has been increasing interest in the use of colloidal silver as remedies for a wide range of ailments, though these claims are disputed. The consumption of large amounts of silver can lead to a darkening of the skin known as argyria.

Silver is a very ductile and malleable (slightly harder than gold) univalent 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 has prevented it from being widely used in place of copper for electrical purposes, though it was used in the electromagnets used for enriching uranium during World War II (mainly because of the wartime shortage of copper).

Pure silver has the highest thermal conductivity, whitest color, the highest optical reflectivity. This metal is stable in pure air and water, but does tarnish when it is exposed to ozone, hydrogen sulfide, or air containing sulfur.

A major use of silver is as a precious metal. Sterling silver is 92.5 % silver, alloyed usually with copper. Jewelry and silverware are traditionally made from this. Silver is used in medals, denoting second place. Some high end musical instruments are made from sterling silver, such as the flute.

The name of United Kingdom monetary unit 'Pound' originally had the value of one troy pound of sterling silver. Silver has been coined to produce money since 700 BC by the Lydians, in the form of electrum. Later, silver was refined and coined in its pure form. The words for "silver" and "money" are the same in at least 14 languages.

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 is normally associated with them.

Its germicidal effects kill many microbial organisms. Its germicidal effects make silver utensils valued, and increase its value as jewelry. The exact process of silver's germicidal effect is still not well understood, although different theories exist.

Folklore and mass culture

Because of the mysticism surrounding silver's lunar associations, as well as the aesthetic qualities of the white, reflective metal that cause it to be associated with purity, silver in European Folklore has long been traditionally believed to be an antidote to various maladies and fictional monsters. Notably, silver was believed to be a repellant against vampires (this primarily originates from its holy connotations; also, mirrors were originally polished silver, and as such, vampires allegedly cannot be seen in them because they have no soul) and it was believed that a werewolf, in his bestial form, could only be killed by a weapon or bullet made of silver, and was equally effective against vampires, as described in Eastern European folklore. This has given rise to the term "silver bullet," which is used to describe things that very effectively deal with one specific problem.

Sterling silver

Fine silver (99.9% pure) is generally too soft for producing large functional objects, and in Sterling the silver is usually alloyed with copper to give strength whilst preserving the ductility of the silver and a high precious metal content. Other metals can replace the copper, usually with the intent to improve various properties of the basic sterling alloy such as reducing casting porosity, eliminating firescale, and increasing resistance to tarnish. These replacement metals include germanium, zinc, platinum as well as a variety of other additives including silicon and boron. A number of alloys claiming firescale and/or tarnish resistance have appeared in recent years sparking heavy competition between the various manufacturers and their different formulations. No one alloy has emerged as an industry leader or standard and ongoing alloy development is a very active area.