Word Origin: Anglo-Saxon Seolfor or siolfur; meaning 'silver', and Latin argentum meaning 'silver'.
Silver (IPA: /ˈsɪlvə(ɹ)/) is a chemical element with the symbol Ag and atomic number 47. A soft white lustrous transition metal, it has the highest electrical and thermal conductivity for a metal. It occurs as a free metal (native silver) as well as various minerals such as argentite and chlorargyrite. Most silver is produced as a by-product of copper, gold, lead, and zinc mining.
Characteristics
- Silver is very ductile and malleable (slightly harder than gold).
- It has the highest electrical conductivity of all metals, even higher than copper.
- Among metals, pure silver has the highest thermal conductivity (only the non-metal diamond's is higher), whitest color, the highest optical reflectivity (although aluminium slightly outdoes it in parts of the visible spectrum), and is a poor reflector of ultraviolet light.
- Silver also has the lowest contact resistance of any metal.
Silver has been known since antiquity. It has long been valued as a precious metal and used in currency, ornaments and jewellery, as well as utensils (hence the term silverware). Silver bullion has the ISO currency code of XAG. 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.
Jewellery and silverware are traditionally made from Sterling silver (Standard silver) an alloy of 92.5% silver with 7.5% copper. Sterling silver is harder than pure silver, and has a lower melting point (893 °C) than either pure silver or pure copper. Britannia silver is an alternative hallmark-quality standard containing 95.8% silver, often used to make silver tableware and wrought plate. Silver is used in medals, denoting second place
Source: Wikipedia
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