Fragments broken off a larger solid body of material
Spall
Spall consists of fragments of a material that break off a larger solid body.
It can be produced by a variety of mechanisms, including as a result of projectile impact, corrosion, weathering, cavitation, or excessive rolling pressure. Spalling and spallation both describe the process of surface failure in which spall is shed.
Text adapted from Wikipedia, CC BY-SA 4.0. Photograph: Maximilian Bühn (see Commons), Wikimedia Commons.