F2-5 Cinder Cone Volcano
A cross-section of a typical cinder cone showing the build-up of a steep slope around a central vent.

A cinder cone is a small, conical volcanic structure that forms around a central vent as a result of an explosive eruption. It is composed primarily of loose pyroclastic material. Most of these ejected basaltic rock fragments are fairly small and take on the appearance of cinders as they harden, hence the name.

Did You Know?
The cinder cone volcano known as Sunset Crater in Arizona was nearly dynamited in 1929 in order to create a landslide for the Hollywood movie Avalanche. Local citizen action lead by H. S. Colton prevented this from happening and resulted in the formation of Sunset Crater National Monument in 1930.

Cinder cone volcanoes have very steep slopes usually ranging between 30–40°. Their size rarely exceeds several hundred meters (approximately 2,000 feet). They are usually formed over a short period of time as a result of one single eruptive event. 50% of all cinder cone volcanoes form in less than 1 month, while 95% are formed in less than a year. Occasionally the cone can remain active for several years. One of the most famous cinder cones in the world is Paricutin Volcano in Mexico. It was actually active for 9 years after starting its eruption in 1943. Most cinder cones have a circular crater at their summit. Cinder cones are the most common of the three types of volcanoes.

A typical cinder cone (213 meters/700 feet high) found at Lassen Volcanic National Park in California, and named, appropriately enough, Cinder Cone.