Backscattered electron image of ash erupted from Pavlof Volcano, AK

Backscattered electron microscope images can be used to view very small particles – in this case, ash that is less than a quarter of a millimeter in length. This ash sample erupted from Pavlof volcano, Alaska. Composed almost exclusively of fresh vesicular glassy particles with few crystals, the ash provides clues about magma formation and ascent.