Silver jewelry makes a wonderful gift for a loved one - as long as you know what you are shopping for! In the world of silver, all that glitters is not, well, silver. Some jewelry is advertised as "silver tone." Silver tone jewelry is costume jewelry and usually contains no real silver at all. It is silver in color, but can be made from so many different combinations of metals that there is no standard of what to expect. Some silver tone is very durable and won't tarnish. Other silver tone pieces are brittle, or tarnish almost immediately. It frequently leaves green markings on the wearer's skin where it contacts perfume or perspiration. "Alpaca Silver" is another type of silver jewelry frequently encountered by consumers. It sounds quite exotic, like some sort of silver mined from South A