A frequently asked question here at the Archaeology @ About.com website concerns an artifact that someone has found, or inherited, or bought somewhere. Among the questions people ask is:
- How do I find out what kind of artifact it is?
- What culture does my artifact come from?
- How old is it?
- Is it a fake?
- How much is it worth?
The first thing you might try is to post the image to our bulletin board.
However, it's very difficult to determine the age or characteristics of an artifact with even the best picture—harder still to determine if it's real or not, so I always suggest that you take the object to an archaeologist to ask them. If you know where the object came from, you might be better off finding a specialist in that area. But if you're clueless, go to the nearest archaeologist of any stripe you can find.
An archaeologist could be as close as the nearest anthropology department of your local university, or the state archaeologist's office, or a nearby museum.
Call first—many archaeologists spend much of the year in the field. If they can, they'll be happy to speak to you—and they won't try to steal the object from you! And if they don't know, they can probably tell you who you can talk to.

