roundness

In geology, roundness refers to the smoothness of particles, a property that, along with form and surface texture, helps determine the transporting agent and depositional environment of sedimentary rocks. It is largely a result of abrasion history, influenced by factors such as the depositional agent, mineralogy, clast size, and transport distance. For instance, windblown and surf zone sands tend to be well-rounded, while glacial sands are angular. Roundness is typically measured by visually comparing grains to standard silhouette profiles. The general definition of roundness is the quality or state of being round, having a curving rather than jagged or angular shape.123