Silver is a white, lustrous and malleable metal used in the manufacture of jewelry, currency and tableware because of its beauty and resistance to corrosion. It is also highly ductile and therefore used in the manufacture of electronic components. Silver occurs in nature in its pure form, but it is also found alloyed with other metals like gold, zinc and lead and is recovered in the refining process.
Sterling silver, an alloy, is most often used in jewelry manufacture. Sterling silver indicates the item contains 92.5% silver combined with 7.5% (usually) copper creating a stronger, more durable silver alloy. Sterling silver is marked .925 indicating its fineness. Some jewelry and many silver coins may be 99.9% pure and marked with a fineness of .999. As with gold, Federal law requires manufacturers to stamp silver items with its fineness as well as a manufacturer’s hallmark.
GoldFellow® buys silver jewelry, coins, bars, rounds, serving pieces and silverware marked .999, .925, Sterling, Sterling Silver, or Ster in the metal. Silver plated means a layer of sterling silver has been bonded to the surface of a base metal. GoldFellow® does not purchase silver plated items. Although some jewelry may use “silver” in its name like, Mexican Silver or Nickel Silver, the item may not contain any silver at all. For example, Nickel Silver is an alloy containing nickel, zinc and copper – no silver content whatsoever. If GoldFellow® receives items which do not test to be silver, they will be returned at no charge.
http://en.wikipedia.org/wiki/Silver – Silver