Photographs and information for a large collection of igneous, metamorphic and sedimentary rocks. Geology.com

These rocks include: andesite, basalt, dacite, obsidian, pumice, rhyolite, scoria, and tuff. Pictures and brief descriptions of some common igneous rock types are shown on this page.

A picture gallery of metamorphic rocks including amphibolite, gneiss, hornfels, marble, novaculite, phyllite, quartzite, schist, skarn, slate and soapstone.

Photos and brief descriptions of some common sedimentary rock types are shown on this page. Chalk is a type of limestone made up of the microscopic calcium carbonate shells of marine …

There are several different types of meteorites! Learn about them in this article by Geoffrey Notkin, meteorite hunter.

Gifts That Rock - What are the most popular gift items in the Geology.com store?

Obsidian is an igneous rock that forms when molten rock material cools so rapidly that atoms are unable to arrange themselves into a crystalline structure. It is an amorphous material known …

Most rocks will not perform well in a rock tumbler; however, a few types of rock can be successfully tumbled by a beginner if the rocks are carefully selected. These easy-to-tumble …

Coal is an organic sedimentary rock that forms from the accumulation and preservation of plant materials, usually in a swamp environment. Coal is a combustible rock and, along with oil and …

Jul 29, 2013 · An introduction to rock art with links to galleries of petroglyphs and pictographs from around the world.