In June 1838 Barry and colleagues undertook a tour of Britain to locate a supply of stone for the building, eventually choosing Magnesian Limestone from the Anston quarry of the Duke of Leeds. Work started on building the river frontage on 1 January 1839, and Barry's wife laid the foundation stone on 27 April 1840. The stone was badly quarried and handled, and with the polluted atmosphere in London it proved to be problematic, with the first signs of deterioration showing in 1849, and extensive renovations required periodically.