Fossils 

Information on Mammal Fossils:  http://paleo.amnh.org/bjburger/fossilmammal/index.html

Photo Gallery of a wide range of fossils, news, links and resource information: http://www.fossilmuseum.net/index.htm

Breaking news about paleontology and fossils:  http://www.foxnews.com/science/evolution/index.html

Locations of Missouri Fossils:  http://www.dnr.mo.gov/pubs/pub665.pdf

Minerals

The History of Salt:  http://www.saltinstitute.org/38.html

The Agate Lexicon:  http://csd.unl.edu/agates/agatelexicon.asp

Minerals of Iowa:  http://www.igsb.uiowa.edu/Browse/minerals/minerals.htm