Although the focus of this assignment is not on art history, you may find that these resources provide at least some of the information you'll need to interpret your object.
Oxford Art Online
This massive reference resource includes the full text of the 34-volume Dictionary of Art. [Note: There is a limit of three simultaneous users.]
Includes these sources for an overview of art related topics.
It's likely that you'll need to think expansively and creatively as you research your chosen object. The following questions will help guide you as you do research:
Who created the object?
When was it created?
How was it created?
Where was it found?
Who would have made use of it? Who wouldn't have made use of it?
If you'd like to do a bit more research beyond what's available in subject encyclopedias, here are a few good strategies to use: