n. A white or colorless crystalline compound, SiO 2, occurring abundantly as quartz, sand, flint, agate, and many other minerals and used to manufacture a wide variety of materials, especially glass and concrete.ilicon dioxide, SiO 2, a compound that occurs widely in rocks and mineral forms, such as quartz, sand, and flint, and is used to make glass, concrete, and other materials.
Greater London is a ceremonial county of England. It was created on 1 April 1965, covering the 32 London boroughs, and excludes the City of London.The region covers 1,572 km 2 (607 sq mi) and had a population of 8,174,000 at the 2011 census. It has the highest GVA per capita in the United Kingdom at Â£37,232.he term London is normally used in reference to Greater London or to the conurbation, but not often to the ancient, tiny City of London. This small area is often referred to as the City or the Square Mile and it forms the main financial district.
The City of London is the largest city based on population and is the capital of the United Kingdom as well as England. London is also one of the largest urban areas in the entire European Union. London's history goes back to Roman times when it was called Londinium.