Methods of manufacture

Bricks may be made from clay, shale, soft slate, calcium silicate, concrete, or shaped from quarried stone.
Clay is the most common material, with modern clay bricks formed in one of three processes - soft mud, dry press, or extruded.
In 2007 a new type of brick was invented, based on fly ash, a by-product of coal power plants.

Brick making at the beginning of the 20th century.