These are not all the resources, just a good start.
They are not ranked in order of preference, just in ABC order for convenience.
1. Atlas of Rocks and Minerals
2. Franklin Institute Rocks and Minerals
3. Gale Discovering Series. Type in the term Minerals or a specific type of mineral (Click on Gale off main library Web page)
4. Grolier Multimedia Encyclopedia. Type in the term Minerals or a specific type of mineral (Click on Grolier Multimedia Encyclopedia off main library Web page)
6. Kennesaw State University Rocks and Minerals Site
7. Minerals Management Service
8. Rocks and Minerals slide show