Collecting Rocks, Gems, and Minerals in the Yahoo! Directory

theImage.com
Includes images and image capture techniques for gemstones and minerals.
www.theimage.com
Suseok.net
Collections of suiseki. In Korean language.
www.suseok.net
Sue's Gemstone World
Includes birthstones, gallery, library, and links.
www.suevematsu.com
Illustrated Dictionary of Jewelry
Includes jewel terms, mineralogy, jewelry manufacturers, jewelry styles, gemstone cuts, etc.
www.allaboutjewels.com/jewel/glossary
Smithsonian Gem & Mineral Collection
Collection of Smithsonian image files of gems and minerals.
www.gimizu.de/sgmcol