Sterling silver is an alloy of silver containing at least 92.5% pure silver with at most 7.5% of other metals, usually copper. The pure silver is too soft for producing large functional objects, and in sterling the silver is usually alloyed with copper to give strength while preserving the ductility of the silver and a high precious metal content. Other metals can replace the copper, usually with the intent to improve various properties of the basic sterling alloy such as reducing casting porosity, eliminating firescale, and increasing resistance to tarnish. These replacement metals include germanium, zinc, platinum as well as a variety of other additives including silicon and boron. A number of alloys claiming firescale and/or tarnish resistance have appeared in recent years sparking heavy competition between the various manufacturers and their different formulations. Gray & Sons features a fine selection of sterling silver flatware, sterling tea sets, sterling hollowware, sterling silverware and various other fine sterling products.