Uses of stones Five main groups of uses of stones; Building and decorative stone – stone used for its resistance to weather or its aesthetic appeal – walls and decorative purposes. Buildings, walls, paving slabs.

Aggregates – stone used for its strong physical properties – crushed and sorted into various sizes for use in concrete, coated with bitumen to make asphalt or used 'dry' as bulk fill in construction. Mostly used in roads, concrete and building products

Industrial purposes – limestone can be used for its chemical (mainly alkaline) properties as calcium carbonate (CaCO3) in farming and manufacturing industry

Lime burning (calcining) – limestone when heated to a high temperature breaks down into lime (calcium oxide) and carbon dioxide gas. It can then be used as a more powerful alkali than limestone (see above) or used as a cement with sand, to make mortar, or as a soil improver in agriculture.

Use of stones in architecture Stone has two distinct architectural faces; In monumental architecture, it stands for wealth, power, and permanence At a domestic scale and based on local craft traditions, it appears as modest, forthright, and natural

Finely worked, accurately cut blocks, sometimes of exotic(FORIGN) origin or polished to a jewel-like finish, characterize monumental architecture while fieldstone, rubble, or roughly-worked stone set in thick mortar beds are more often associated with modest works

McKim, Mead & White: Post Office

Stone cladding is often used to impart a kind of traditional legitimacy to otherwise Modern buildings

UN Secretariat The United Nations Secretariat Building (1953) clad in white marble and glass.

stone use declined in the three decades following World War II in favor of more technologically-advanced materials The 1980s saw an explosion in the use of stone cladding Stone has also been "re-invented" by several 20th-century architects who have developed wall systems combining aspects of stone masonry and concrete technology