Geology

A free informational and educational guide to rocks, minerals, gemstones and jewelry. Provides detailed information and photos of hundreds of minerals and gemstones.

Established in 1998, IGS is the largest online gemology resource and community.  The Learning Center has a library of information related to gemstones, gemology, gemstone jewelry information, reference charts, and lapidary information.  A very useful offering is the Gemstone Encyclopedia featuring 304 Gemstones. There is also an information page on birthstones.