What exactly is Sterling silver?

Sterling Silver is silver with a small amount of copper. Pure silver, like pure gold, is too soft to stay in its form, so it is combined with copper to form sterling silver. The additional metal adds strength and enhances silver's natural gloss. Sterling silver is the combination of 92.5 percent pure silver and 7.5 percent copper, and is stamped "92.5" or "925".

One common test for sterling silver is to put a magnet near it. If the magnet sticks, the piece cannot be sterling, although it could be silver-plated nickel or brass.