Contains over 4,000 individual mineral species descriptions with links and an image library.

From Virginia Energy

From the USGS

Contains worldwide data on minerals, mineral collecting, mineral localities and other mineralogical information.

From the National Park Service.

Provides scientific stewardship, products, and services for geophysical data from the Sun to the Earth and Earth's sea floor and solid earth environment, including Earth observations from space.

A web-based data management system for geochemical and petrological sample-based data.

From USGS.

From the Geology Department at the University of North Carolina.

Provides quality geoscience images to the public, educators, and the geoscience community.
From the American Geological Institute (AGI).

All photos are in the public domain, but the USGS requests that users credit the photographer and the USGS when using a photo.