If you own any silver jewelry, you may have noticed a small stamp on the metal that reads “925”. What does 925 on jewelry mean? It means that you’ve got a quality sterling silver piece on your hands!
What is sterling silver?
Pure silver is a precious metal too malleable for use in jewelry. Therefore, it is often alloyed with other metals, such as copper, to make it suitable for jewelry use. The resulting alloy is known as sterling silver, and is composed of 92.5% pure silver, and 7.5% other metals, typically copper.
This 92.5% pure silver composition of sterling silver is why genuine sterling silver pieces are often stamped with the numbers 925. If you see this marking on a piece of silver jewelry, you can be assured that it meets the quality standard for sterling silver. On occasion, a piece of sterling silver jewelry will be too small to bear a .925 stamp. This does not necessarily mean the piece is not sterling silver; a jeweler or other jewelry retailer should be able to confirm the composition of a piece of jewelry.
A 925 stamp on jewelry is not the only marking that signifies sterling silver. Other acceptable quality marks include “sterling,” “sterling silver,” “ster,” and “.925.” These markings are not to be confused with a maker’s mark, which is sometimes present on jewelry manufactured by a certain brand.
Why does sterling silver tarnish?
Many owners of sterling silver jewelry notice that their piece beginning to tarnish over time. They then question whether their jewelry is authentic sterling silver. Tarnishing happens naturally as a process of oxidation, when the metal reacts with the oxygen in the air to dull the surface of the jewelry, often giving it a black color. Pure silver is not very reactive, and ordinarily would not react with the air so easily. However, copper reacts with oxygen easily by nature, and since sterling silver is usually composed of 7.5% copper, the jewelry becomes subject of tarnish more easily.