Reference books, like encyclopedias and handbooks, provide general information about a subject, and will be great to use for background information about your mineral.
In the library:
Encyclopedia of Mineralogy / edited by Keith Frye
Handbook of mineralogy / John W. Anthony
Rock-forming minerals / W.A. Deer, R.A. Howie, J. Zussman
Rock forming minerals in thin section / H. Pichler and C. Schmitt-Riegraf ; translated by L. Hoke
Practical handbook of physical properties of rocks and minerals / edited by Robert S. Carmichael
QE431.6.P5 P73 1989
The resources below are for background information from the International Mineralogical Association.
Note: This IMA stuff won't itself count for your peer-reviewed article requirement (though the "key reference" articles would). However, it can still be good for background information.
Part of your assignment is to find scholarly articles, also sometimes called "peer-reviewed" or "refereed" articles. To find articles like these, start with the Georef, listed below.
**Don't forget: If you're stuck finding articles about your mineral, you can expand your search to include articles related to the properties of your mineral you learned about in the reference books above, like the group your mineral is a part of.
If you find an article you want that's not in the library, never fear! You can use Interlibrary Loan (ILL) to get a copy of that article from another library. It's usually fast, and they can usually send you the article you want as a PDF, so you don't even have to come to the library!
For more information, and to register your ILL account (totally free, of course), visit our Interlibrary Loan (ILL) page.