Silver is a transition metal with atomic number 47 and element symbol Ag. This shiny metal is valued for its beauty, rarity, and properties. Here are silver facts, including its history, uses, and sources.
- The word silver comes from the Anglo-Saxon word for the metal, seolfor.
- There is no word in English that rhymes with silver.
- The element symbol Ag comes from the Latin name for silver, argentum. This word, in turn, comes from the Sanskrit word argunus, which means “shining.”
- Silver is one of the seven metals known to ancient humans. The others are gold, copper, tin, iron, lead, and mercury.
- The reason primitive people knew about silver is because it is one of the elements that exists in pure form naturally. Silver also occurs as a natural alloy with gold called electrum. Otherwise, silver forms compounds found in copper, zinc, and lead ores.
- Silver was rarer and more expensive than gold until around the fifteenth century BC. Because of its value, it was probably the first form of money.
- The words for silver and money are the same in at least 14 languages.
Essential Silver Facts
- Silver is the element with atomic number 47 and atomic weight of 107.8682. It is a transition metal that has an oxidation state of +1.
- The element has a melting point of 961.78 °C or1763.2 °F and a boiling point of 2162 °C or 3924 °F.
- Silver is the shiniest element. Polished silver reflects 95% of visible light. However, silver only poorly reflects ultraviolet light.
- Silver is the best electrical conductor of all the elements. However, copper is much less expensive and nearly as good a conductor, so it is used more often in wiring.
- Silver has the highest thermal conductivity of any metal.
- Silver is highly ductile, meaning it can be drawn into thin wires. One ounce of silver can be drawn into a wire 8000 feet long. Only gold has a higher ductility.
- Silver is so malleable that it single silver grain (about 65 milligrams) can be pressed into a sheet that is thinner than the average sheet of paper.
- Silver is harder than gold, but softer than copper.
- Natural silver consists of two stable isotopes: silver-107 and silver-109. Silver-107 accounts for slightly more than half the natural abundance (51.84%). Near-equal isotope abundance is rare in nature.
- Silver remains shiny in pure water or oxygen gas, but it tarnishes or oxidizes in air from a reaction with sulfur compounds.
- Pure silver isn’t very toxic to humans, but it’s a good antibacterial agent. Silver compounds are less dangerous than heavy metal compounds, but can still cause illness and potentially respiratory arrest. Excessive colloidal silver can cause acute silver poisoning and possibly organ damage and tumor development. In large doses, absorption of silver by body tissues leads to a condition called argyria. Argyria makes the skin, eyes, and mucous membranes appear ashy blue-gray. Although the color is disturbing, argyria doesn’t appear to cause lasting health effects.
- The leading producers of silver are Mexico and Peru. The United States, Canada, Russia, China, and Australia also mine silver. Most silver is a by-product of copper, zinc, and lead mining.
Uses of Silver
- Silver finds use in jewelry, currency, silverware, and dentistry.
- Because of its low reactivity, silver is safe to use as a food decoration.
- Because of its high reflectivity, silver is used in mirrors, solar cells, telescopes, and microscopes.
- Because it is naturally antimicrobial, silver aids water filtration and air conditioning.
- Because of its thermal conductivity, silver wires are embedded in automobile rear windows to defrost ice quickly.
- Silver nanoparticles are used to make electrically conductive printing ink.
- The ancient Phoenicians stored wine, water, and oil in silver, which acted as a natural disinfectant. Silver is still used today as an antimicrobial agent in clothing, cosmetics, wound dressings, and medications.
- The silver compound silver iodide (AgI) is used for cloud seeding. It stimulates clouds to release rain and may help control hurricanes.
- Silver nitrate is important in photography. It makes celluloid film sensitive to light.
- Silver compounds containing nitrogen and oxygen are important explosives. Example compounds include silver fulminate, silver oxalate, silver(II) oxide, silver azide, silver amide, and silver acetylide. Heat, pressure, or drying activate some of these compounds, but sometimes all it takes is exposure to light. Under the right conditions, they may explode spontaneously.
Types of Silver
- Pure or nearly pure silver (99%) is called fine silver. However, pure silver is too soft for most uses, so it’s usually alloyed with other elements to increase its hardness and durability.
- Most silver in use is sterling silver. This is an alloy made of 92.5% silver. The other 7.5% usually is copper, but other metals maybe used. It’s called sterling silver in reference to silver pennies used by the Normans that were decorated with stars or sterre. They were starling or sterling silver pennies.
- Britannia silver is 95.8% silver and 4.2% copper. It’s used in silverware and jewelry.
- Mexican silver is 95% silver and 5% copper.
- Alpaca silver is silver-colored, but doesn’t contain any silver at all.
More Silver Facts
- The crescent moon is one common alchemy symbol for silver.
- Silver and gold form in supernovae. Smaller exploding stars produce silver, while larger ones make more gold.
- Silver is used as a food coloring with the name E174. It’s also used in Indian food as a decorative foil layer called “varak”.
- The crystal structure of silver is a face-centered cubic.
- Silver is diamagnetic, meaning it is repelled by a magnetic field.
- Because of its low reactivity in air, silver is one of the noble metals.
- In folklore, silver can kill a witch or werewolf or aid in accessing the fairy realm.
- The earliest minted silver coins came from Lydia in Asia Minor circa 600 BC. Technically, they were electrum coins.
- Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. Amsterdam. ISBN 978-0-08-037941-8.
- Hammond, C. R. (2004). “The Elements,” in Handbook of Chemistry and Physics (81st ed.). Chemical Rubber Company Publishing. Boca Raton (FL).
- Silber, William L. (2019). The Story of Silver: How the White Metal Shaped America and the Modern World. Princeton, NJ: Princeton University Press.
- Weast, Robert (1984). Handbook of Chemistry and Physics. Chemical Rubber Company Publishing. Boca Raton (FL). ISBN 0-8493-0464-4.