Grain Size

Grain size refers to the diameter of individual mineral particles or crystals in a rock or soil. It indicates how fine or coarse the material is: fine-grained materials have tiny particles, while coarse-grained ones have larger grains. Grain size affects a material's properties, such as strength, permeability, and texture. For example, sand has larger grains than clay, making it more permeable to water. Geologists use grain size to classify rocks and sediments, helping to understand their formation processes and environmental history.