Summarize this article in one sentence.
Items advertised as silver and sold internationally should be stamped based on its silver content. If there is no stamp, be leery. It may be still be pure silver, but created in a country that doesn't require stamping. Look at the silver piece with a magnifying glass. International sellers of silver will stamp silver as 925, 900 or 800. These numbers indicate the percentage of fine silver in the piece. 925 means that the piece is 92.5 percent silver. A stamp of 900 or 800 means the piece is 90 percent or 80 percent silver, and is often called "coin" silver.

Summary:
Look for a stamp. Evaluate the international silver stamp rating.