Note:  Do not rely on this information. It is very old.


Agglomerate, a coarse, usually unstratified accumulation of lava and other rocks, in angular or sub-angular masses, generally in a glassy or semi crystalline ground-mass, which has accumulated at the close of an eruption in the chimney or bottom of the crater of a volcano, thus forming a "neck," or central mass resisting denudation, in a volcanic hill.