Sterling silver

Sterling silver is a silver alloy with a purity of 92.5% by weight of silver and 7.5% by weight of other metals, usually copper. The sterling silver standard has a minimum millesimal fineness of 925.

History

Sterling silver originated in continental Europe in the 12th century. The first explicit mention of the standard is in a royal charter of the Worshipful Company of Goldsmiths, granted by Edward I of England in 1300 which specified that sterling silver consisted of 92.5% silver and 7.5% copper.

Properties

Sterling silver is harder than pure silver, and has a lower melting point (893 °C) than pure silver or pure copper. The addition of copper makes the silver tougher (less likely to bend or break) but also causes it to tarnish more quickly, due to chemical reactions between the silver and sulfur in the air.

Uses

Sterling silver is used for jewelry, silverware, musical instruments, and dental fillings. It is also used in photography for its light-sensitive properties.

Care and cleaning

Sterling silver tarnishes when exposed to air, especially air that contains sulfur. It can be cleaned with a soft cloth and silver polish, or by soaking in a solution of baking soda and water.

Hallmarking

In many countries, sterling silver items are stamped with a hallmark to indicate their purity. The hallmark for sterling silver varies from country to country, but often includes the number 925.

See also

• Silver
• Silver alloy
• Copper
• Hallmark