Grain size Grain size Grain size (or particle size) is the diameter of individual grains of sediment, or the lithified particles in clastic rocks. The term may also be applied to other granular materials. This is different from the crystallite size, which refers to the size of a single crystal inside a particle or grain. A single grain can be composed of several crystals. Granular material can range from very small colloidal particles, through clay, silt, sand, gravel, and cobbles, to boulders. Size ranges define limits of classes that are given names in the Wentworth scale (or Udden–Wentworth scale) used in the
Godalming of the town centre steep hills reach 95 m (311.67 ft) AOD from 40-45m (131.23-147.63 ft) AOD in the town centre itself. In terms of rock and mineral structure, the soil is Gault Clay superimposed by Upper Greensand, Claygate Beds and Bagshot Sands; throughout the narrow east-west middle valley of Godalming and its wide northeast suburbs (Farncombe and Catteshall) the rocky head geological deposit is also found; angular pieces of rock and soil derived locally from the extensive frost-shattering of rocks and the subsequent movement of this material down valley slopes. Soil is mostly, i.e. on the upper slopes of