Building material is any material which is used for construction purposes. Many naturally occurring substances, such as clay, rocks, sand, and wood, even twigs and leaves, have been used to construct buildings.
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles. It is defined by size, being finer than gravel and coarser than silt.
Bricks made by shaping a plastic mass of clay and water, which is then hardened by drying and firing, are among the oldest and most enduring of mankind’s building materials. Until comparatively recent times the clay was dug, the bricks were made and the kilns set or drawn by manual labour with help from animal power. About 100 years ago, the first effective machines for brick production appeared, and the trend towards mechanization of clay winning, making and handling operations has continued at an increasing pace to the present day.