Brick

Some bricks are made for specific purposes and are made of certain raw materials, formed in a particular shape, or with added special textures or glazes. Common brick is the everyday building brick. They are not made of special materials, and do not have special marks, color, or texture. Common brick is typically red and sometimes used as a "backup" brick, depending on the quality. Face brick is often applied on top of common backup brick. Face brick can be obtained in a variety of colors, has a uniform surface appearance and color, is more durable, and is graded according to its ability to withstand freezing temperatures and moisture. Refractory bricks are made from fireclays—clays with a high alumina or silica content or nonclay minerals such as bauxite, zircon, silicon carbide, or dolomite. Fireclays are heat resistant and are used in various types of furnaces, kilns, and fireplaces. Calcium silicate bricks are often made in areas where clay is not readily available. Glazed bricks are made primarily for walls in buildings such as dairies, hospitals, and laboratories, where easy cleaning is necessary.