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18 mag 2024 · Silver is often found in ores along with other metals like lead, zinc, copper, and gold. Some of the most common silver-bearing ores include argentite (silver sulfide), cerargyrite (silver chloride), and galena (a lead ore often containing significant amounts of silver).
5 gen 2024 · Most of the world’s silver mines are in North and South America, but there are also significant deposits in Poland, Turkey, and Australia. The world’s largest silver mine is KGHM’s copper mine in Poland, which produced 42.3 million ounces of silver in 2021. Mexico has four of the top ten silver-producing mines globally.
Silver is extremely ductile, and can be drawn into a wire one atom wide. Silver is similar in its physical and chemical properties to its two vertical neighbours in group 11 of the periodic table: copper, and gold.
- Overview
- Properties, uses, and occurrence
- Compounds
silver (Ag), chemical element, a white lustrous metal valued for its decorative beauty and electrical conductivity. Silver is located in Group 11 (Ib) and Period 5 of the periodic table, between copper (Period 4) and gold (Period 6), and its physical and chemical properties are intermediate between those two metals.
Together with gold and the platinum-group metals, silver is one of the so-called precious metals. Because of its comparative scarcity, brilliant white colour, malleability, ductility, and resistance to atmospheric oxidation, silver has long been used in the manufacture of coins, ornaments, and jewelry. Silver has the highest known electrical and thermal conductivity of all metals and is used in fabricating printed electrical circuits and as a vapour-deposited coating for electronic conductors; it is also alloyed with such elements as nickel or palladium for use in electrical contacts. Silver also finds use as a catalyst for its unique ability to convert ethylene to ethylene oxide, which is a precursor of many organic compounds. Silver is one of the noblest—that is, least chemically reactive—of the transition elements.
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Facts You Should Know: The Periodic Table Quiz
Silver ornaments and decorations have been found in royal tombs dating back as far as 4000 bce. It is probable that both gold and silver were used as money by 800 bce in all countries between the Indus and the Nile.
Silver is widely distributed in nature, but the total amount is quite small when compared with other metals; the metal constitutes 0.05 part per million of Earth’s crust. Practically all sulfides of lead, copper, and zinc contain some silver. Silver-bearing ores may contain amounts of silver from a trace to several thousand troy ounces per avoirdupois ton, or about 10 percent.
Unlike gold, silver is present in many naturally occurring minerals. For silver the more important deposits commercially are such compounds as the minerals tetrahedrite and argentite (silver sulfide, Ag2S), which is usually associated with other sulfides such as those of lead and copper, as well as several other sulfides, some of which contain antimony as well. Silver is found generally in lead ores, copper ores, and cobalt arsenide ores and is also frequently associated with gold in nature. Most silver is derived as a by-product from ores that are mined and processed to obtain these other metals. Deposits of native (chemically free, or uncombined) silver are also commercially important.
For silver the preeminently important oxidation state in all of its ordinary chemistry is the state +1, although the states +2 and +3 are known.
Silver compounds include silver chloride (AgCl), silver bromide (AgBr), and silver iodide (AgI). Each of these salts is used in photography. Silver chloride serves as the light-sensitive material in photographic printing papers and, together with silver bromide, in certain films and plates. The iodide is also used in the manufacture of photographic papers and films, as well as in cloud seeding for artificial rainmaking and in some antiseptics. All three halides are derived from silver nitrate (AgNO3), which is the most important of the inorganic silver salts. Besides these other salts, silver nitrate is also the starting material for the production of the silver cyanide used in silver plating.
- The Editors of Encyclopaedia Britannica
Silver can be found all over the world, but is generally concentrated around volcanic and hydrothermal activity. Silver is rarely found in pure form – be it nuggets, lodes or placer deposits – but as alloys, mineral deposits, or in trace amounts of other ores.
4 giorni fa · A majority of the world’s silver mines are located in Peru, Bolivia, Mexico, China, Australia, Chile, Poland, and Serbia. The pure form of silver can be found in the Earth’s crust, with the occurrence only being 0.08 parts per million.
Silver is mined as an ore of sulfide, acanthite, or argentite. Silver is found with copper, copper-nickel, lead, and lead-zinc. Therefore, its production requires smelting. Only 27% of silver derives from mining activities, where silver comprises the primary source of revenue.
