The document discusses sphericity and roundness in sediments. Roundness refers to how rounded the edges and corners of grains have become due to abrasion during transportation, with more rounding indicating longer transportation. Sphericity refers to how close a grain's original shape is to a sphere, and is an inherited property rather than one changed by transportation, so needle-like grains will still be needle-like after transport. Both properties provide clues about a sediment's history of weathering and transportation.