lapilli

thumb|right|340px|Lapilli on Kilauea

Lapilli (: lapillus) is a size classification of tephra, which is material that falls out of the air during a volcanic eruption or during some meteorite impacts. Lapilli is Latin for "little stones". It consists of fresh pumice or scoria, volcanic glass such as Pele’s hair, lithic fragments of rock or crystal or as ash aggregates such as accretionary lapilli, cored accretionary lapilli, ash pellets or ash coated clasts.