Cornerstone

Cornerstone, ceremonial building block, usually placed ritually in the outer wall of a building to commemorate its dedication. Sometimes the stone is solid, with date or other inscription. More typically, it is hollowed out to contain metal receptacles for newspapers, photographs, currency, books, or other documents reflecting current customs, with a view to their historical use when the building is remodeled or demolished. Until the development of modern construction, the stone was usually at a...