Clay brick units are typically used in brick masonry construction. They are typically composed of soft clay extruded into shapes in a manufacturing plant, and are available in various colors, sizes and textures.
The standard for clay masonry units is ASTM C216. In this standard, and in building specifications, clay units are categorized by grade (NW, MW or SW) and type (FBA, FBS and FBX).

Technical Datasheets