Coade stone in the context of "Westminster Bridge"

Cast stone or reconstructed stone is a refined artificial stone, a form of precast concrete. It is used as a building material to simulate natural-cut masonry in architectural features such as facings and trim; for statuary; and for garden ornaments. It may replace natural building stones including limestone, brownstone, sandstone, bluestone, granite, slate, and travertine. Cast stone can be made from white or grey cements, manufactured or natural sands, crushed stone or natural gravels, and can be coloured with mineral colouring pigments. It is cheaper and more uniform than natural stone, and allows transporting the bulk materials and casting near the place of use, which is cheaper than transporting and carving very large pieces of stone.

Grog, also known as firesand and chamotte, is a raw material usually made from crushed and ground potsherds, reintroduced into crude clay to temper it before making ceramic ware. It has a high percentage of silica and alumina.

It is normally available as a powder or chippings, and is an important ingredient in Coade stone.

The South Bank Lion is an 1837 sculpture in Central London. Since 1966 it has stood next to County Hall, on the South Bank of the River Thames. It is a significant depiction of a lion, along with the four that surround Nelson's Column in Trafalgar Square just across the river.

The statue is about 13 feet (4.0 m) long and 12 feet (3.7 m) high, and weighs about 13 tonnes (14 tons). It was cast in 1837, the year of Queen Victoria's accession, of Coade stone, one of the earliest types of artificial stone. The material is very resistant to weathering, and the fine details of the lion's modelling still remain clear after decades of exposure to the corrosive effects of London's severe air pollution, the infamous pea soup fog, prior to the passage of the Clean Air Act 1956. The statue was made in separate parts and cramped together on an iron frame. It was formerly known as the Red Lion, as it was painted that colour between 1951 and 1966.