Geology

"The Smithsonian Institution mineral and gem collection consists of approximately 350,000 mineral specimens and 10,000 gems, making it one of the largest of its kind in the world. Meteorites, rocks, ores, gems, and minerals databases can be searched from the Mineral Sciences Collection Search page."

GIA's mission is to ensure the public trust in gems and jewelry by upholding the highest standards of integrity, academics, science, and professionalism through education, research, laboratory services, and instrument development.

Descriptions of minerals with images and links.

Created by the U.S. Bureau of Mines, "this overview presents historical and reference information on the principal gemstones and their production in certain States."

This National Geographic website provides basic information about rocks.

Created by the USGS, this site contains information on various rocks, minerals, naming igneous rocks, a glossary, and rock classification chart.