Databases

Web Mineral - Extensive mineral database containing crystallography, chemical composition, physical and optical properties, Dana classification, Strunz classification, mineral name origins, mineral locality information, and alphabetical listing of all known valid mineral species.
http://webmineral.com/

Amethyst Galleries' Mineral Gallery - Provides a searchable database of mineral and gemstone descriptions, images, and specimens.
http://www.galleries.com/

MinMax - Mineral Information System - Searchable database of minerals and worldwide collecting localities. Languages: English, Deutsch
http://minmax.net/index.php3?lang=US

Athena Mineralogy - Systematic classification of minerals and searchable database.
http://un2sg4.unige.ch/athena/mineral/mineral.html

Mineral 1.0 - An online rock and mineral quiz/test, as well as a browsable online mineral database with descriptions and pictures.
http://www.spaceman.ca/mineral/

Virtual Atlas of Opaque and Ore Minerals - Information about the identification and study of minerals.
http://www.smenet.org/opaque%2Dore/

Mindat - Searchable mineral database with physical and chemical properties as well as locality information.
http://www.mindat.org/

Mineral Spectroscopy - Information about color in minerals and the spectroscopy of minerals (mineral absorption spectra).
http://minerals.gps.caltech.edu/

MineralDB Collectors Software - Mineral software to catalogue collections and research mineral facts using the extensive knowledge base.
http://www.mineraldb.com/