Soil the mineral components of soil; it consists of rock fragments, primarily quartz particles, ranging in size from in diameter. Silt ranges in size from . Clay cannot be resolved by optical microscopes as its particles are or less in diameter and a thickness of only 10 angstroms (10 m). In medium-textured soils, clay is often washed downward through the soil profile (a process called eluviation) and accumulates in the subsoil (a process called illuviation). There is no clear relationship between the size of soil mineral components and their mineralogical nature: sand and silt particles can be calcareous as well as
Wattle and daub driven into the ground with small branches (wattle) interwoven between them make the structural frame of the wall. Mud or an adobe clay (daub) is covered outside. To provide additional weather protection, the wall is usually plastered. Wattle and daub Wattle and daub is a composite building material used for making walls, in which a woven lattice of wooden strips called "wattle" is "daubed" with a sticky material usually made of some combination of wet soil, clay, sand, animal dung and straw. Wattle and daub has been used for at least 6,000 years and is still an important construction material