Four types of pyroclastic materials include ash, lapilli, lava blocks and floating rocks. Pyroclastic materials are ejected during a volcano. Ash is the most common type of pyroclastic material.
Lava blocks are large rock pieces that are ejected from a volcano. They are solid and angular shaped, with some as large as a car in size. Lapilli are small, pea-sized ejections that all types of lava produce. Floating rock occurs when pumice, another type of pyroclasic material, becomes buoyant. It is able to float for thousands of miles. It is also found on shores near the site of the volcanic eruption.