Silver
Silver is a lustrous white metal that has been prized since antiquity for its beauty and workability, and it holds the record for the highest electrical and thermal conductivity of any metal known. Unlike iron, it never rusts, though it does slowly tarnish as trace sulfur compounds in the air react with its surface. That rare combination of scarcity, shine and corrosion resistance made it one of humanity's first precious metals.
- Group · Period
- 11 · 5
- At room temp
- solid
- Melts at
- 1234.93 K
- Density
- 10.501 g/cm³
- Discovered
- Ancient
Uses
For most of history silver’s main roles were jewelry, tableware and coinage, and it’s still a leading choice for all three today, prized for a shine that resists dulling from ordinary air exposure. Its unmatched reflectivity also made it the standard coating for household and telescope mirrors, since a thin silver layer reflects visible light more completely than almost any other surface. Silver compounds have long been valued for their antibacterial effect too, and silver is still used today in wound dressings, catheter coatings and water-purification filters.
In modern industry, silver’s electrical conductivity makes it essential in small but critical amounts: it’s used in high-reliability electrical contacts, in the conductive paste printed onto solar cells, and in brazing alloys that join metal parts. Before the rise of digital sensors, silver halide crystals were also the light-sensitive component at the heart of virtually all photographic film.
History
Silver has no discoverer because it was already known before recorded history began. Ancient civilizations across Anatolia, Mesopotamia, Egypt, Greece and the Americas mined and refined it, often using a heating process called cupellation to separate it from lead ores, and it became one of the earliest metals used as currency and a store of wealth. Its chemical symbol, Ag, comes from the Latin word for silver, argentum, while the English name traces back to an old Germanic root — a reminder that silver was already deeply woven into human culture long before chemistry gave it a formal place on the periodic table.
Fun facts
- Silver conducts electricity and heat better than any other metal, including copper and gold.
- Silver tarnishing has nothing to do with oxygen — the dark layer is silver sulfide, formed by trace sulfur compounds in the air, and it can simply be polished off.
- Humans have mined and worked silver for well over five thousand years, long before anyone understood it as a chemical element.
Frequently asked questions
Why does silver tarnish instead of rusting like iron?
Rust is iron reacting with oxygen and moisture, but silver barely reacts with oxygen at all. What silver does react with is trace hydrogen sulfide and other sulfur compounds in the air, which slowly build up a thin dark layer of silver sulfide on the surface. Unlike rust, that layer sits only on top of the metal, so polishing restores the shine underneath without any silver being lost to corrosion.
Why is silver still used in electronics when it's so expensive?
Because only tiny amounts are needed to get the benefit. A thin silver-plated contact or a trace of silver paste on a circuit board carries current with less resistance than any cheaper metal could manage, so manufacturers use just enough silver where conductivity really matters rather than building whole components from it.
Who discovered silver?
No one, in the way we talk about later elements. Silver occurs naturally and is easy to extract from its ores by heating, so ancient peoples were mining and shaping it thousands of years before the concept of a chemical element existed — it simply has no single discoverer.
Compounds
7 notable compounds containing Ag
- AgBrsalt
Silver bromide
A pale yellow, light-sensitive salt whose crystals darken on exposure to light as silver ions are reduced to metallic silver.
Used for: Light-sensitive component of traditional photographic film
- AgClsalt
Silver chloride
An almost completely insoluble white silver salt that darkens rapidly under light as it breaks down into metallic silver. That light sensitivity made it central to early photographic chemistry.
Used for: Light-sensitive coating in traditional photographic film
- AgIsalt
Silver iodide
A pale yellow, extremely insoluble silver salt whose crystal structure closely resembles that of ice, letting it act as a nucleation point for ice crystals inside clouds.
Used for: Cloud seeding to encourage rain or snow
- AgNO3salt
Silver nitrate
A water-soluble silver salt made by dissolving silver metal in nitric acid. It darkens on exposure to light or organic matter as it slowly decomposes to metallic silver, and serves as the main starting point for making most other silver compounds.
Used for: Photographic film, silver plating, and medical antiseptics
- Ag2Ooxide
Silver oxide
A dark brown-black solid formed when silver ions react with hydroxide in solution. It is mildly basic and breaks back down into metallic silver and oxygen gas when heated.
Used for: Positive electrode material in silver-oxide button-cell batteries
- Ag2Smineral
Silver sulfide
A dark, highly insoluble compound that forms as a thin black film whenever silver metal contacts trace sulfur compounds in the air. It is, quite literally, the tarnish on silverware.
Used for: Occurs naturally as the mineral acanthite; the cause of silver tarnish
- Ag2Temineral
Silver telluride
A dark, metallic-looking compound of silver and tellurium that occurs naturally as the mineral hessite, often found alongside gold in low-temperature ore deposits.
Used for: Studied as a topological insulator and thermoelectric material
Isotopes
41 known isotopes
Swipe to see all columns →
| Isotope | Natural abundance | Half-life | Decay mode | Mass excess | Binding energy / nucleon | Decay width |
|---|---|---|---|---|---|---|
| Ag-107 stable | 51.839% | Stable | — | -88,406.7 keV | 8,553.9 keV | — |
| Ag-109 stable | 48.161% | Stable | — | -88,719.43 keV | 8,547.92 keV | — |
Show all 41 isotopes
| Ag-92 | — | — | Proton emission, Electron capture / beta-plus decay, ECP | -37,530 keV | 8,080 keV | — |
| Ag-93 | — | 228 ns | Proton emission, Electron capture / beta-plus decay, ECP | -46,400 keV | 8,175 keV | 2.00 × 10-9 eV |
| Ag-94 | — | 26 ms | Electron capture / beta-plus decay (100%), ECP | -52,402 keV | 8,238 keV | 1.75 × 10-14 eV |
| Ag-95 | — | 1.75 s | Electron capture / beta-plus decay (100%), ECP | -59,906 keV | 8,315 keV | 2.61 × 10-16 eV |
| Ag-96 | — | 4.40 s | Electron capture / beta-plus decay (100%), ECP (8.5%) | -64,511.65 keV | 8,360.29 keV | 1.04 × 10-16 eV |
| Ag-97 | — | 25.5 s | Electron capture (100%) | -70,904.03 keV | 8,423.21 keV | 1.79 × 10-17 eV |
| Ag-98 | — | 47.5 s | Electron capture / beta-plus decay (100%), ECP (0.0011%) | -73,066.43 keV | 8,441.69 keV | 9.61 × 10-18 eV |
| Ag-99 | — | 124 s | Electron capture / beta-plus decay (100%) | -76,712.48 keV | 8,474.77 keV | 3.68 × 10-18 eV |
| Ag-100 | — | 2.01 m | Electron capture / beta-plus decay (100%) | -78,137.97 keV | 8,484.99 keV | 3.78 × 10-18 eV |
| Ag-101 | — | 11.1 m | Electron capture / beta-plus decay (100%) | -81,334.38 keV | 8,512.55 keV | 6.85 × 10-19 eV |
| Ag-102 | — | 12.9 m | Electron capture / beta-plus decay (100%) | -82,246.7 keV | 8,517.17 keV | 5.89 × 10-19 eV |
| Ag-103 | — | 65.7 m | Electron capture / beta-plus decay (100%) | -84,802.7 keV | 8,537.65 keV | 1.16 × 10-19 eV |
| Ag-104 | — | 69.2 m | Electron capture / beta-plus decay (100%) | -85,116.47 keV | 8,536.19 keV | 1.10 × 10-19 eV |
| Ag-105 | — | 41.29 d | Electron capture / beta-plus decay (100%) | -87,070.85 keV | 8,550.37 keV | 1.28 × 10-22 eV |
| Ag-106 | — | 23.96 m | Electron capture / beta-plus decay (99.5%), Beta-minus decay (1%) | -86,942.4 keV | 8,544.64 keV | 3.17 × 10-19 eV |
| Ag-108 | — | 2.382 m | Beta-minus decay (97.15%), Electron capture / beta-plus decay (2.85%) | -87,606.79 keV | 8,542.03 keV | 3.19 × 10-18 eV |
| Ag-110 | — | 24.56 s | Beta-minus decay (99.7%), Electron capture (0.3%) | -87,457.31 keV | 8,532.11 keV | 1.86 × 10-17 eV |
| Ag-111 | — | 7.45 d | Beta-minus decay (100%) | -88,215.45 keV | 8,534.79 keV | 7.09 × 10-22 eV |
| Ag-112 | — | 3.130 h | Beta-minus decay (100%) | -86,583.73 keV | 8,516.08 keV | 4.05 × 10-20 eV |
| Ag-113 | — | 5.37 h | Beta-minus decay (100%) | -87,026.83 keV | 8,516.07 keV | 2.36 × 10-20 eV |
| Ag-114 | — | 4.6 s | Beta-minus decay (100%) | -84,930.81 keV | 8,493.78 keV | 9.92 × 10-17 eV |
| Ag-115 | — | 20.0 m | Beta-minus decay (100%) | -84,982.59 keV | 8,490.56 keV | 3.80 × 10-19 eV |
| Ag-116 | — | 230 s | Beta-minus decay (100%) | -82,542.66 keV | 8,465.91 keV | 1.98 × 10-18 eV |
| Ag-117 | — | 72.8 s | Beta-minus decay (100%) | -82,181.92 keV | 8,459.45 keV | 6.27 × 10-18 eV |
| Ag-118 | — | 3.76 s | Beta-minus decay (100%) | -79,553.8 keV | 8,433.89 keV | 1.21 × 10-16 eV |
| Ag-119 | — | 2.1 s | Beta-minus decay (100%) | -78,645.76 keV | 8,423.21 keV | 2.17 × 10-16 eV |
| Ag-120 | — | 1.23 s | Beta-minus decay (100%), Beta-minus, neutron emission (0.003%) | -75,651.51 keV | 8,395.33 keV | 3.71 × 10-16 eV |
| Ag-121 | — | 0.78 s | Beta-minus decay (100%), Beta-minus, neutron emission (0.08%) | -74,402.83 keV | 8,382.33 keV | 5.85 × 10-16 eV |
| Ag-122 | — | 0.529 s | Beta-minus decay (99.8%), Beta-minus, neutron emission (0.186%) | -71,106.12 keV | 8,352.76 keV | 8.62 × 10-16 eV |
| Ag-123 | — | 0.299 s | Beta-minus decay (100%), Beta-minus, neutron emission (0.62%) | -69,568.58 keV | 8,337.97 keV | 1.53 × 10-15 eV |
| Ag-124 | — | 191 ms | Beta-minus decay (100%), Beta-minus, neutron emission (1.3%) | -66,229.95 keV | 8,308.9 keV | 2.39 × 10-15 eV |
| Ag-125 | — | 159 ms | Beta-minus decay (100%), Beta-minus, neutron emission | -64,519.94 keV | 8,293.32 keV | 2.87 × 10-15 eV |
| Ag-126 | — | 52 ms | Beta-minus decay (100%), Beta-minus, neutron emission | -60,720 keV | 8,261 keV | 8.77 × 10-15 eV |
| Ag-127 | — | 109 ms | Beta-minus decay (100%) | -58,650 keV | 8,244 keV | 4.19 × 10-15 eV |
| Ag-128 | — | 58 ms | Beta-minus decay (100%), Beta-minus, neutron emission | -54,710 keV | 8,211 keV | 7.87 × 10-15 eV |
| Ag-129 | — | 46 ms | Beta-minus decay (100%), Beta-minus, neutron emission (0%) | -51,870 keV | 8,188 keV | 9.92 × 10-15 eV |
| Ag-130 | — | 42 ms | Beta-minus decay (100%), B-2N, Beta-minus, neutron emission | -45,898 keV | 8,142 keV | 1.09 × 10-14 eV |
| Ag-131 | — | 35 ms | Beta-minus decay (100%), Beta-minus, neutron emission, B-2N | -40,750 keV | 8,102 keV | 1.30 × 10-14 eV |
| Ag-132 | — | 28 ms | Beta-minus decay (100%), Beta-minus, neutron emission, B-2N | -34,400 keV | 8,053 keV | 1.63 × 10-14 eV |