Advertising

Tuff

What is Welded Tuff?

Welded Tuff is a rock that is composed of materials that were ejected from a volcano, fell to Earth, and then lithified into a rock. It is usually composed mainly of volcanic ash and sometimes contains larger size particles such as cinders.

Tuff: The specimen shown is about two inches (five centimeters) across.

The rock photos above were taken by Ann Bryant and are copyright by Geology.com.

Igneous Rocks

Andesite

Basalt

Diorite

Gabbro

Granite

Obsidian

Pegmatite

Peridotite

Pumice

Rhyolite

Scoria

Tuff

Rock Tumblers: Step-by-step guide to tumble-polishing rocks into gemstones. And an article: How to select a tumbler.

Igneous Rock Photo Gallery: A collection of igneous rock pictures and short descriptions.

Photos of Kilauea Lava: Spectacular USGS photos of lava flows pouring into the Pacific.

Volcanoes! A page that links to all of our volcano articles and to the best volcano information that we could find.

Sliding Rocks - Racetrack Playa: How these rocks slide across a dry lake bed is a mystery. Photo © iStockphoto / Stephan Hoerold.

Mount Vesuvius: An interesting article with photos and maps that describes the volcano's eruption history, geologic hazards, plate tectonics and more.

Metamorphic Rocks: Photos and facts about foliated and non-foliated metamorphic rocks.

Sedimentary Rocks: Photos and facts about clastic, chemical and organic sedimentary rocks.