Pure silver, also known as fine silver, is made up of 99.9% silver, while 925 Sterling Silver usually has a purity of 92.5% silver. Silver is a very soft metal, which makes pure silver unsuitable for jewelry making as it will easily scratch, dent, and change shape. In order to make the silver harder and more durable, copper and other metals are added to the pure silver. 925 Sterling Silver is one of these mixes, usually with a purity of 92.5% silver. This percentage is the reason why we call it 925 Sterling Silver or 925 Silver. The remaining 7.5% of the mixture is usually copper, although sometimes it may consist of other metals such as zinc or nickel.