A cinder cone is a type of volcano that is made of loose rock fragments that have been ejected from the volcano.
Cinder cones are the smallest types of volcanoes.
They have very steep slopes. Cinder cones are often associated with other larger volcanoes and are often found in groups. Composite Cones Composite cones or stratovolcanoes are large, nearly symmetrical structures composed of alternating lava flows and deposits of rock fragments. Composite cones are steeper than cinder cones at the top but become more gently sloping at the base. In the US these are the volcanoes in the Cascade Mountains including Mt. Saint Helens, which erupted in 1980.