Silver

The best electrical and thermal conductor of any element, ahead of copper by only a few percent, and those few percent are almost never worth a hundred times the price — it wins only where the margin matters, as in solar cell gridlines and RF plating. Sterling silver is 92.5% silver with copper making up the rest, and it is the copper that tarnishes. Silver tarnish is silver sulfide from traces of sulfur in the air, not oxide, which is why it blackens faster near rubber bands and boiled eggs.

Properties

Density

10,490 kg/m³ — 10.49 g/cm³

Melting point

961.8 °C

Tensile strength

140–190 MPa

Young's modulus

83 GPa

Thermal conductivity

429 W/(m·K)

Thermal expansion

18.9 µm/(m·K)

Floats in water

No

Magnetic

No

What it is used for

• Solar cell conductive paste
• High-current relay and switch contacts
• Brazing alloys
• Tableware, jewellery and mirrors

How it compares

Does it rust?

Silver does not rust — rust is iron oxide specifically — but it does corrode, forming its own oxide or salts over time.

Is it magnetic?

Silver is not ferromagnetic. It is often assumed to be because it is a metal, but most metals are not — only iron, nickel, cobalt and a few alloys are attracted to an ordinary magnet.