Pyroklastisches Material refers to the fragments of rock and volcanic debris that are ejected during a volcanic eruption. This material is formed by the explosive activity of a volcano and can vary in size, composition, and texture. The term "pyroclastic" comes from the Greek words pur (fire) and klastos (broken), which together mean "broken by fire."

Here are the main types of pyroklastisches Material:

1. Ash: Fine particles of rock and minerals, typically smaller than 2 mm in diameter. Ash is often carried by wind over long distances and can cause significant disruption to air travel and infrastructure.

2. Lapilli: Small stones or pebbles ranging in size from 2 mm to 64 mm (about 0.08 to 2.5 inches). These can fall close to the eruption site, and depending on their composition, they can be sharp and cause damage to buildings, crops, or machinery.

3. Volcanic Bombs: Larger pieces of molten or semi-molten rock, often bigger than 64 mm in diameter. These can be ejected in the form of liquid or semi-solid blobs and can solidify mid-air, often creating large, jagged rocks when they land.

4. Pumice: A porous, light rock formed from lava that cools quickly. It is often light enough to float on water due to its air-filled bubbles. Pumice is commonly used as an abrasive material.

5. Tuff: A type of rock formed from the compaction of volcanic ash and other fine pyroclastic materials that have been deposited by volcanic eruptions.

Pyroklastisches Material is crucial for understanding the dynamics of volcanic eruptions and can be used to study past volcanic activity. It also plays a role in the formation of certain types of landscapes, such as volcanic plateaus and craters.