When found on jewelry, "Italy 925" means that the piece is made of sterling silver. Sterling silver is comprised of 92.5 percent pure silver and a mixture of other metals.
Most of the time, other metals like platinum or zinc are included in the mix along with the silver to increase the tensile strength of the jewelry. Pure silver is quite malleable and can be damaged with little to no force, making sterling an attractive option if the wearer is rough on her jewelry. Silver jewelry must contain at least 92 percent silver to be considered sterling, according to reputable jewlers.